Stdlib · ocaml-base-compiler 4.12.1

ocaml-base-compiler

Official release 4.12.1

Version

IN THIS PACKAGE

library bigarray
- module Bigarray
  - module Array0
  - module Array1
  - module Array2
  - module Array3
  - module Genarray
library dynlink
- module Dynlink
library ocamlbytecomp
- module Bytegen
- module Bytelibrarian
- module Bytelink
- module Bytepackager
- module Compile
- module Emitcode
- module Errors
- module Instruct
- module Maindriver
- module Printinstr
library ocamlcommon
- module Arg_helper
  - module Make
    
    argument 1-S
    
    module Key
    
    module Map
    
    module Value
- module Ast_helper
  - module Attr
  - module Cf
  - module Ci
  - module Cl
  - module Const
  - module Csig
  - module Cstr
  - module Ctf
  - module Cty
  - module Exp
  - module Incl
  - module Mb
  - module Md
  - module Mod
  - module Ms
  - module Mtd
  - module Mty
  - module Of
  - module Opn
  - module Pat
  - module Rf
  - module Sig
  - module Str
  - module Te
  - module Typ
  - module Type
  - module Val
  - module Vb
- module Ast_invariants
- module Ast_iterator
- module Ast_mapper
- module Attr_helper
- module Binutils
- module Btype
  - module For_copy
  - module TypeHash
  - module TypeMap
  - module TypeSet
- module Build_path_prefix_map
- module Builtin_attributes
- module Bytesections
- module CamlinternalMenhirLib
  - module Convert
    
    module Simplified
  - module Engine
    
    module Make
    
    argument 1-T
    
    module Log
  - module EngineTypes
    
    module type ENGINE
    
    module type INCREMENTAL_ENGINE_START
    
    module type MONOLITHIC_ENGINE
    
    module type TABLE
    
    module Log
  - module ErrorReports
  - module General
  - module IncrementalEngine
    
    module type EVERYTHING
    
    module type INCREMENTAL_ENGINE
    
    module type INSPECTION
    
    module type SYMBOLS
  - module InfiniteArray
  - module InspectionTableFormat
    
    module type TABLES
  - module InspectionTableInterpreter
    
    module Make
    
    argument 1-TT
    
    argument 2-IT
    
    argument 3-ET
    
    module Log
    
    argument 4-E
    
    module Symbols
    
    argument 1-T
  - module LinearizedArray
  - module PackedIntArray
  - module Printers
    
    module Make
    
    argument 1-I
    
    argument 2-User
  - module RowDisplacement
  - module StaticVersion
  - module TableFormat
    
    module type TABLES
  - module TableInterpreter
    
    module MakeEngineTable
    
    argument 1-T
    
    module Log
- module Ccomp
- module Clflags
  - module Compiler_pass
  - module Float_arg_helper
  - module Int_arg_helper
- module Cmi_format
- module Cmt2annot
- module Cmt_format
- module Compenv
- module Compile_common
- module Compmisc
- module Config
- module Consistbl
  - module Make
    
    argument 1-Module_name
    
    module Map
    
    module Set
    
    module Tbl
- module Ctype
  - module TypePairs
  - module Unification_trace
- module Datarepr
- module Debuginfo
  - module Scoped_location
- module Depend
- module Dll
- module Docstrings
  - module WithMenhir
- module Domainstate
- module Env
- module Envaux
- module Ident
  - module Map
  - module Set
  - module T
  - module Tbl
- module Identifiable
  - module Make
    
    argument 1-T
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module type Map
    
    module T
  - module Pair
    
    argument 1-A
    
    argument 2-B
  - module type S
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module type Set
    
    module T
  - module type Tbl
    
    module T
  - module type Thing
- module Includeclass
- module Includecore
- module Includemod
- module Int_replace_polymorphic_compare
- module Lambda
- module Lexer
- module Load_path
  - module Dir
- module Local_store
- module Location
- module Longident
- module Main_args
  - module type Arg_list
  - module type Bytecomp_options
  - module type Bytetop_options
  - module type Common_options
  - module type Compiler_options
  - module type Core_options
  - module Default
    
    module Main
    
    module Odoc_args
    
    module Optmain
    
    module Opttopmain
    
    module Topmain
  - module Make_bytecomp_options
    
    argument 1-_
  - module Make_bytetop_options
    
    argument 1-_
  - module Make_ocamldoc_options
    
    argument 1-_
  - module Make_optcomp_options
    
    argument 1-_
  - module Make_opttop_options
    
    argument 1-_
  - module type Ocamldoc_options
  - module type Optcommon_options
  - module type Optcomp_options
  - module type Opttop_options
  - module type Toplevel_options
- module Makedepend
- module Matching
- module Meta
- module Misc
  - module Color
  - module EnvLazy
  - module Error_style
  - module Int_literal_converter
  - module LongString
  - module Magic_number
  - module Stdlib
    
    module Array
    
    module List
    
    module Option
    
    module String
    
    module Map
    
    module Set
    
    module Tbl
- module Mtype
- module Numbers
  - module Float
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module Int
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module Int16
  - module Int8
- module Opcodes
- module Oprint
- module Parmatch
  - module Compat
    
    argument 1-_
- module Parse
- module Parser
  - module Incremental
  - module MenhirInterpreter
- module Path
  - module Map
  - module Set
- module Patterns
  - module General
  - module Half_simple
  - module Head
  - module Non_empty_row
  - module Simple
- module Persistent_env
  - module Consistbl
  - module Persistent_signature
- module Pparse
- module Pprintast
- module Predef
- module Primitive
- module Printast
- module Printlambda
- module Printpat
- module Printtyp
  - module Conflicts
  - module Naming_context
  - module Out_name
- module Printtyped
- module Profile
- module Rec_check
- module Runtimedef
- module Simplif
- module Strongly_connected_components
  - module Make
    
    argument 1-Id
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module type S
    
    module Id
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
- module Stypes
- module Subst
- module Switch
  - module CtxStore
    
    argument 1-A
  - module type CtxStored
  - module Make
    
    argument 1-Arg
  - module type S
  - module Store
    
    argument 1-A
  - module type Stored
- module Symtable
- module Syntaxerr
- module Targetint
- module Tast_iterator
- module Tast_mapper
- module Terminfo
- module Translattribute
- module Translclass
- module Translcore
- module Translmod
- module Translobj
- module Translprim
- module Type_immediacy
  - module Violation
- module Typeclass
- module Typecore
  - module Datatype_kind
- module Typedecl
- module Typedecl_immediacy
- module Typedecl_properties
- module Typedecl_separability
- module Typedecl_unboxed
- module Typedecl_variance
- module Typedtree
- module Typemod
  - module Sig_component_kind
  - module Signature_names
- module Typeopt
- module Types
  - module Concr
  - module Meths
  - module Separability
  - module TypeOps
  - module Uid
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module Variance
  - module Vars
- module Typetexp
- module Untypeast
- module Warnings
library ocamlmiddleend
- module Alias_analysis
- module Allocated_const
- module Augment_specialised_args
  - module Definition
  - module Make
    
    argument 1-_
  - module type S
  - module What_to_specialise
- module Backend_var
  - module Provenance
  - module With_provenance
- module Build_export_info
- module Clambda
- module Clambda_primitives
- module Closure
- module Closure_conversion
- module Closure_conversion_aux
  - module Env
  - module Function_decls
    
    module Function_decl
- module Closure_element
  - module Map
  - module Set
  - module T
  - module Tbl
- module Closure_id
  - module Map
  - module Set
  - module T
  - module Tbl
- module Closure_middle_end
- module Closure_offsets
- module Closure_origin
  - module Map
  - module Set
  - module T
  - module Tbl
- module Compilation_unit
  - module Map
  - module Set
  - module T
  - module Tbl
- module Compilenv
- module Convert_primitives
- module Effect_analysis
- module Export_id
  - module Map
  - module Set
  - module T
  - module Tbl
- module Export_info
- module Export_info_for_pack
- module Extract_projections
- module Find_recursive_functions
- module Flambda
  - module Constant_defining_value
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module With_free_variables
- module Flambda_invariants
- module Flambda_iterators
- module Flambda_middle_end
- module Flambda_to_clambda
- module Flambda_utils
  - module Switch_storer
- module Freshening
  - module Project_var
- module Id_types
  - module type BaseId
  - module Id
  - module UnitId
    
    argument 1-_
    
    argument 2-Compilation_unit
    
    module Compilation_unit
- module Import_approx
- module Inconstant_idents
- module Initialize_symbol_to_let_symbol
- module Inline_and_simplify
- module Inline_and_simplify_aux
  - module Env
  - module Result
- module Inlining_cost
  - module Benefit
  - module Threshold
  - module Whether_sufficient_benefit
- module Inlining_decision
- module Inlining_stats
  - module Closure_stack
- module Inlining_stats_types
  - module Decision
  - module Inlined
  - module Not_inlined
  - module Not_specialised
  - module Prevented
  - module Specialised
- module Inlining_transforms
- module Internal_variable_names
- module Invariant_params
- module Lift_code
- module Lift_constants
- module Lift_let_to_initialize_symbol
- module Linkage_name
  - module Map
  - module Set
  - module T
  - module Tbl
- module Mutable_variable
  - module Map
  - module Set
  - module T
  - module Tbl
- module Parameter
  - module List
  - module Map
  - module Set
  - module T
  - module Tbl
- module Pass_wrapper
- module Printclambda
- module Printclambda_primitives
- module Projection
  - module Map
  - module Set
  - module T
  - module Tbl
- module Ref_to_variables
- module Remove_free_vars_equal_to_args
- module Remove_unused_arguments
- module Remove_unused_closure_vars
- module Remove_unused_program_constructs
- module Semantics_of_primitives
- module Set_of_closures_id
  - module Map
  - module Set
  - module T
  - module Tbl
- module Set_of_closures_origin
  - module Map
  - module Set
  - module T
  - module Tbl
- module Share_constants
- module Simple_value_approx
- module Simplify_boxed_integer_ops
  - module Simplify_boxed_int32
  - module Simplify_boxed_int64
  - module Simplify_boxed_nativeint
- module Simplify_common
- module Simplify_primitives
- module Static_exception
  - module Map
  - module Set
  - module T
  - module Tbl
- module Symbol
  - module Map
  - module Set
  - module T
  - module Tbl
- module Tag
  - module Map
  - module Set
  - module T
  - module Tbl
- module Traverse_for_exported_symbols
- module Un_anf
- module Unbox_closures
- module Unbox_free_vars_of_closures
- module Unbox_specialised_args
- module Var_within_closure
  - module Map
  - module Set
  - module T
  - module Tbl
- module Variable
  - module Map
  - module Pair
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module Set
  - module T
  - module Tbl
library ocamloptcomp
- module Afl_instrument
- module Alias_analysis
- module Allocated_const
- module Arch
- module Asmgen
- module Asmlibrarian
- module Asmlink
- module Asmpackager
- module Augment_specialised_args
  - module Definition
  - module Make
    
    argument 1-_
  - module type S
  - module What_to_specialise
- module Available_regs
- module Backend_var
  - module Provenance
  - module With_provenance
- module Branch_relaxation
  - module Make
    
    argument 1-T
    
    module Cond_branch
- module Branch_relaxation_intf
  - module type S
    
    module Cond_branch
- module Build_export_info
- module CSE
  - cse
- module CSEgen
  - cse_generic
- module Clambda
- module Clambda_primitives
- module Closure
- module Closure_conversion
- module Closure_conversion_aux
  - module Env
  - module Function_decls
    
    module Function_decl
- module Closure_element
  - module Map
  - module Set
  - module T
  - module Tbl
- module Closure_id
  - module Map
  - module Set
  - module T
  - module Tbl
- module Closure_middle_end
- module Closure_offsets
- module Closure_origin
  - module Map
  - module Set
  - module T
  - module Tbl
- module Cmm
- module Cmm_helpers
- module Cmmgen
- module Cmmgen_state
- module Coloring
- module Comballoc
- module Compilation_unit
  - module Map
  - module Set
  - module T
  - module Tbl
- module Compilenv
- module Compute_ranges
  - module Make
    
    argument 1-S
    
    module Index
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
    
    module Key
    
    module Map
    
    module Set
    
    module Range_info
    
    module Subrange_info
    
    module Subrange_state
    
    module Range
    
    module Subrange
- module Compute_ranges_intf
  - module type S
    
    module Index
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
    
    module Key
    
    module Map
    
    module Set
    
    module Range
    
    module Range_info
    
    module Subrange
    
    module Subrange_info
    
    module Subrange_state
  - module type S_functor
    
    module Index
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
    
    module Key
    
    module Map
    
    module Set
    
    module Range_info
    
    module Subrange_info
    
    module Subrange_state
  - module type S_range_info
  - module type S_subrange_info
  - module type S_subrange_state
- module Convert_primitives
- module Deadcode
- module Effect_analysis
- module Emit
- module Emitaux
- module Export_id
  - module Map
  - module Set
  - module T
  - module Tbl
- module Export_info
- module Export_info_for_pack
- module Extract_projections
- module Find_recursive_functions
- module Flambda
  - module Constant_defining_value
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module With_free_variables
- module Flambda_invariants
- module Flambda_iterators
- module Flambda_middle_end
- module Flambda_to_clambda
- module Flambda_utils
  - module Switch_storer
- module Freshening
  - module Project_var
- module Id_types
  - module type BaseId
  - module Id
  - module UnitId
    
    argument 1-_
    
    argument 2-Compilation_unit
    
    module Compilation_unit
- module Import_approx
- module Inconstant_idents
- module Initialize_symbol_to_let_symbol
- module Inline_and_simplify
- module Inline_and_simplify_aux
  - module Env
  - module Result
- module Inlining_cost
  - module Benefit
  - module Threshold
  - module Whether_sufficient_benefit
- module Inlining_decision
- module Inlining_stats
  - module Closure_stack
- module Inlining_stats_types
  - module Decision
  - module Inlined
  - module Not_inlined
  - module Not_specialised
  - module Prevented
  - module Specialised
- module Inlining_transforms
- module Interf
- module Internal_variable_names
- module Interval
- module Invariant_params
- module Lift_code
- module Lift_constants
- module Lift_let_to_initialize_symbol
- module Linear
- module Linear_format
- module Linearize
- module Linkage_name
  - module Map
  - module Set
  - module T
  - module Tbl
- module Linscan
- module Liveness
- module Mach
- module Mutable_variable
  - module Map
  - module Set
  - module T
  - module Tbl
- module Optcompile
- module Opterrors
- module Optmaindriver
- module Parameter
  - module List
  - module Map
  - module Set
  - module T
  - module Tbl
- module Pass_wrapper
- module Printclambda
- module Printclambda_primitives
- module Printcmm
- module Printlinear
- module Printmach
- module Proc
- module Projection
  - module Map
  - module Set
  - module T
  - module Tbl
- module Ref_to_variables
- module Reg
  - module Map
  - module Raw_name
  - module Set
- module Reg_availability_set
- module Reg_with_debug_info
  - module Debug_info
  - module Map_distinguishing_names_and_locations
  - module Set
  - module Set_distinguishing_names_and_locations
- module Reload
- module Reloadgen
  - reload_generic
- module Remove_free_vars_equal_to_args
- module Remove_unused_arguments
- module Remove_unused_closure_vars
- module Remove_unused_program_constructs
- module Schedgen
  - scheduler_generic
- module Scheduling
- module Selectgen
  - module Coeffect
  - module Effect
  - module Effect_and_coeffect
  - selector_generic
- module Selection
- module Semantics_of_primitives
- module Set_of_closures_id
  - module Map
  - module Set
  - module T
  - module Tbl
- module Set_of_closures_origin
  - module Map
  - module Set
  - module T
  - module Tbl
- module Share_constants
- module Simple_value_approx
- module Simplify_boxed_integer_ops
  - module Simplify_boxed_int32
  - module Simplify_boxed_int64
  - module Simplify_boxed_nativeint
- module Simplify_common
- module Simplify_primitives
- module Spill
- module Split
- module Static_exception
  - module Map
  - module Set
  - module T
  - module Tbl
- module Strmatch
  - module type I
  - module Make
    
    argument 1-_
- module Symbol
  - module Map
  - module Set
  - module T
  - module Tbl
- module Tag
  - module Map
  - module Set
  - module T
  - module Tbl
- module Traverse_for_exported_symbols
- module Un_anf
- module Unbox_closures
- module Unbox_free_vars_of_closures
- module Unbox_specialised_args
- module Var_within_closure
  - module Map
  - module Set
  - module T
  - module Tbl
- module Variable
  - module Map
  - module Pair
    
    module Map
    
    module Set
    
    module T
    
    module Tbl
  - module Set
  - module T
  - module Tbl
- module X86_dsl
  - module D
  - module I
- module X86_gas
- module X86_masm
- module X86_proc
library ocamltoplevel
- module Genprintval
  - module type EVALPATH
  - module Make
    
    argument 1-O
    
    argument 2-_
  - module type OBJ
  - module type S
- module Topdirs
- module Toploop
- module Topmain
- module Trace
library odoc_info
- module Odoc_analyse
- module Odoc_ast
  - module Analyser
    
    argument 1-_
  - module Typedtree_search
- module Odoc_class
- module Odoc_comments
  - module Basic_info_retriever
  - module type Texter
- module Odoc_comments_global
- module Odoc_config
- module Odoc_control
- module Odoc_cross
- module Odoc_dep
  - module Dep
- module Odoc_env
- module Odoc_exception
- module Odoc_extension
- module Odoc_global
- module Odoc_info
  - module Class
  - module Dep
  - module Exception
  - module Extension
  - module Global
  - module Module
  - module Name
  - module Parameter
  - module Scan
    
    scanner
  - module Search
  - module Type
  - module Value
- module Odoc_inherit
- module Odoc_lexer
- module Odoc_merge
- module Odoc_messages
- module Odoc_misc
- module Odoc_module
- module Odoc_name
  - module Map
- module Odoc_parameter
- module Odoc_parser
- module Odoc_print
- module Odoc_scan
  - scanner
- module Odoc_search
  - module P_name
  - module type Predicates
  - module Search
    
    argument 1-P
  - module Search_by_name
- module Odoc_see_lexer
- module Odoc_sig
  - module Analyser
    
    argument 1-_
  - module type Info_retriever
  - module Signature_search
- module Odoc_str
- module Odoc_text
  - module Texter
- module Odoc_text_lexer
- module Odoc_text_parser
- module Odoc_type
- module Odoc_types
- module Odoc_value
library stdlib
- module CamlinternalAtomic
- module CamlinternalFormat
- module CamlinternalFormatBasics
- module CamlinternalLazy
- module CamlinternalMod
- module CamlinternalOO
- module Stdlib
  - module Arg
  - module Array
  - module ArrayLabels
  - module Atomic
  - module Bigarray
    
    module Array0
    
    module Array1
    
    module Array2
    
    module Array3
    
    module Genarray
  - module Bool
  - module Buffer
  - module Bytes
  - module BytesLabels
  - module Callback
  - module Char
  - module Complex
  - module Digest
  - module Either
  - module Ephemeron
    
    module GenHashTable
    
    module MakeSeeded
    
    argument 1-H
    
    module K1
    
    module Make
    
    argument 1-H
    
    module MakeSeeded
    
    argument 1-H
    
    module K2
    
    module Make
    
    argument 1-H1
    
    argument 2-H2
    
    module MakeSeeded
    
    argument 1-H1
    
    argument 2-H2
    
    module Kn
    
    module Make
    
    argument 1-H
    
    module MakeSeeded
    
    argument 1-H
    
    module type S
    
    module type SeededS
  - module Filename
  - module Float
    
    module Array
    
    module ArrayLabels
  - module Format
  - module Fun
  - module Gc
    
    module Memprof
  - module Genlex
  - module Hashtbl
    
    module type HashedType
    
    module Make
    
    argument 1-H
    
    module MakeSeeded
    
    argument 1-H
    
    module type S
    
    module type SeededHashedType
    
    module type SeededS
  - module Int
  - module Int32
  - module Int64
  - module LargeFile
  - module Lazy
  - module Lexing
  - module List
  - module ListLabels
  - module Map
    
    module Make
    
    argument 1-Ord
    
    module type OrderedType
    
    module type S
  - module Marshal
  - module MoreLabels
    
    module Hashtbl
    
    module type HashedType
    
    module Make
    
    argument 1-H
    
    module MakeSeeded
    
    argument 1-H
    
    module type S
    
    module type SeededHashedType
    
    module type SeededS
    
    module Map
    
    module Make
    
    argument 1-Ord
    
    module type OrderedType
    
    module type S
    
    module Set
    
    module Make
    
    argument 1-Ord
    
    module type OrderedType
    
    module type S
  - module Nativeint
  - module Obj
    
    module Closure
    
    module Ephemeron
    
    module Extension_constructor
  - module Oo
  - module Option
  - module Parsing
  - module Pervasives
  - module Printexc
    
    module Slot
  - module Printf
  - module Queue
  - module Random
    
    module State
  - module Result
  - module Scanf
    
    module Scanning
  - module Seq
  - module Set
    
    module Make
    
    argument 1-Ord
    
    module type OrderedType
    
    module type S
  - module Stack
  - module StdLabels
  - module Stream
  - module String
  - module StringLabels
  - module Sys
    
    module Immediate64
    
    module type Immediate
    
    module Make
    
    argument 1-Immediate
    
    argument 2-Non_immediate
    
    module type Non_immediate
  - module Uchar
  - module Unit
  - module Weak
    
    module Make
    
    argument 1-H
    
    module type S
library str
- module Str
library threads
- module Condition
- module Event
- module Mutex
- module Semaphore
  - module Binary
  - module Counting
- module Thread
- module ThreadUnix
library unix
- module Unix
  - module LargeFile
- module UnixLabels
  - module LargeFile

Module Stdlib

Exceptions

val raise : exn -> 'a

Raise the given exception value

val raise_notrace : exn -> 'a

A faster version raise which does not record the backtrace.

since 4.02.0

val invalid_arg : string -> 'a

Raise exception Invalid_argument with the given string.

val failwith : string -> 'a

Raise exception Failure with the given string.

exception Exit

The Exit exception is not raised by any library function. It is provided for use in your programs.

exception Match_failure of string * int * int

Exception raised when none of the cases of a pattern-matching apply. The arguments are the location of the match keyword in the source code (file name, line number, column number).

exception Assert_failure of string * int * int

Exception raised when an assertion fails. The arguments are the location of the assert keyword in the source code (file name, line number, column number).

exception Invalid_argument of string

Exception raised by library functions to signal that the given arguments do not make sense. The string gives some information to the programmer. As a general rule, this exception should not be caught, it denotes a programming error and the code should be modified not to trigger it.

exception Failure of string

Exception raised by library functions to signal that they are undefined on the given arguments. The string is meant to give some information to the programmer; you must not pattern match on the string literal because it may change in future versions (use Failure _ instead).

exception Not_found

Exception raised by search functions when the desired object could not be found.

exception Out_of_memory

Exception raised by the garbage collector when there is insufficient memory to complete the computation. (Not reliable for allocations on the minor heap.)

exception Stack_overflow

Exception raised by the bytecode interpreter when the evaluation stack reaches its maximal size. This often indicates infinite or excessively deep recursion in the user's program.

Before 4.10, it was not fully implemented by the native-code compiler.

exception Sys_error of string

Exception raised by the input/output functions to report an operating system error. The string is meant to give some information to the programmer; you must not pattern match on the string literal because it may change in future versions (use Sys_error _ instead).

exception End_of_file

Exception raised by input functions to signal that the end of file has been reached.

exception Division_by_zero

Exception raised by integer division and remainder operations when their second argument is zero.

exception Sys_blocked_io

A special case of Sys_error raised when no I/O is possible on a non-blocking I/O channel.

exception Undefined_recursive_module of string * int * int

Exception raised when an ill-founded recursive module definition is evaluated. The arguments are the location of the definition in the source code (file name, line number, column number).

Comparisons

val (=) : 'a -> 'a -> bool

e1 = e2 tests for structural equality of e1 and e2. Mutable structures (e.g. references and arrays) are equal if and only if their current contents are structurally equal, even if the two mutable objects are not the same physical object. Equality between functional values raises Invalid_argument. Equality between cyclic data structures may not terminate. Left-associative operator, see Ocaml_operators for more information.

val (<>) : 'a -> 'a -> bool

Negation of Stdlib.(=). Left-associative operator, see Ocaml_operators for more information.

val (<) : 'a -> 'a -> bool

See Stdlib.(>=). Left-associative operator, see Ocaml_operators for more information.

val (>) : 'a -> 'a -> bool

See Stdlib.(>=). Left-associative operator, see Ocaml_operators for more information.

val (<=) : 'a -> 'a -> bool

See Stdlib.(>=). Left-associative operator, see Ocaml_operators for more information.

val (>=) : 'a -> 'a -> bool

Structural ordering functions. These functions coincide with the usual orderings over integers, characters, strings, byte sequences and floating-point numbers, and extend them to a total ordering over all types. The ordering is compatible with ( = ). As in the case of ( = ), mutable structures are compared by contents. Comparison between functional values raises Invalid_argument. Comparison between cyclic structures may not terminate. Left-associative operator, see Ocaml_operators for more information.

val compare : 'a -> 'a -> int

compare x y returns 0 if x is equal to y, a negative integer if x is less than y, and a positive integer if x is greater than y. The ordering implemented by compare is compatible with the comparison predicates =, < and > defined above, with one difference on the treatment of the float value Stdlib.nan. Namely, the comparison predicates treat nan as different from any other float value, including itself; while compare treats nan as equal to itself and less than any other float value. This treatment of nan ensures that compare defines a total ordering relation.

compare applied to functional values may raise Invalid_argument. compare applied to cyclic structures may not terminate.

The compare function can be used as the comparison function required by the Set.Make and Map.Make functors, as well as the List.sort and Array.sort functions.

val min : 'a -> 'a -> 'a

Return the smaller of the two arguments. The result is unspecified if one of the arguments contains the float value nan.

val max : 'a -> 'a -> 'a

Return the greater of the two arguments. The result is unspecified if one of the arguments contains the float value nan.

val (==) : 'a -> 'a -> bool

e1 == e2 tests for physical equality of e1 and e2. On mutable types such as references, arrays, byte sequences, records with mutable fields and objects with mutable instance variables, e1 == e2 is true if and only if physical modification of e1 also affects e2. On non-mutable types, the behavior of ( == ) is implementation-dependent; however, it is guaranteed that e1 == e2 implies compare e1 e2 = 0. Left-associative operator, see Ocaml_operators for more information.

val (!=) : 'a -> 'a -> bool

Negation of Stdlib.(==). Left-associative operator, see Ocaml_operators for more information.

Boolean operations

val not : bool -> bool

The boolean negation.

val (&&) : bool -> bool -> bool

The boolean 'and'. Evaluation is sequential, left-to-right: in e1 && e2, e1 is evaluated first, and if it returns false, e2 is not evaluated at all. Right-associative operator, see Ocaml_operators for more information.

val (&) : bool -> bool -> bool

deprecated
Stdlib.(&&) should be used instead. Right-associative operator, see Ocaml_operators for more information.

val (||) : bool -> bool -> bool

The boolean 'or'. Evaluation is sequential, left-to-right: in e1 || e2, e1 is evaluated first, and if it returns true, e2 is not evaluated at all. Right-associative operator, see Ocaml_operators for more information.

val or : bool -> bool -> bool

deprecated
Stdlib.(||) should be used instead. Right-associative operator, see Ocaml_operators for more information.

Debugging

val __LOC__ : string

__LOC__ returns the location at which this expression appears in the file currently being parsed by the compiler, with the standard error format of OCaml: "File %S, line %d, characters %d-%d".

since 4.02.0

val __FILE__ : string

__FILE__ returns the name of the file currently being parsed by the compiler.

since 4.02.0

val __LINE__ : int

__LINE__ returns the line number at which this expression appears in the file currently being parsed by the compiler.

since 4.02.0

val __MODULE__ : string

__MODULE__ returns the module name of the file being parsed by the compiler.

since 4.02.0

val __POS__ : string * int * int * int

__POS__ returns a tuple (file,lnum,cnum,enum), corresponding to the location at which this expression appears in the file currently being parsed by the compiler. file is the current filename, lnum the line number, cnum the character position in the line and enum the last character position in the line.

since 4.02.0

val __FUNCTION__ : string

__FUNCTION__ returns the name of the current function or method, including any enclosing modules or classes.

since 4.12.0

val __LOC_OF__ : 'a -> string * 'a

__LOC_OF__ expr returns a pair (loc, expr) where loc is the location of expr in the file currently being parsed by the compiler, with the standard error format of OCaml: "File %S, line %d, characters %d-%d".

since 4.02.0

val __LINE_OF__ : 'a -> int * 'a

__LINE_OF__ expr returns a pair (line, expr), where line is the line number at which the expression expr appears in the file currently being parsed by the compiler.

since 4.02.0

val __POS_OF__ : 'a -> (string * int * int * int) * 'a

__POS_OF__ expr returns a pair (loc,expr), where loc is a tuple (file,lnum,cnum,enum) corresponding to the location at which the expression expr appears in the file currently being parsed by the compiler. file is the current filename, lnum the line number, cnum the character position in the line and enum the last character position in the line.

since 4.02.0

Composition operators

val (|>) : 'a -> ( 'a -> 'b ) -> 'b

Reverse-application operator: x |> f |> g is exactly equivalent to g (f (x)). Left-associative operator, see Ocaml_operators for more information.

since 4.01

val (@@) : ( 'a -> 'b ) -> 'a -> 'b

Application operator: g @@ f @@ x is exactly equivalent to g (f (x)). Right-associative operator, see Ocaml_operators for more information.

since 4.01

Integer arithmetic

Integers are Sys.int_size bits wide. All operations are taken modulo 2^Sys.int_size. They do not fail on overflow.

val (~-) : int -> int

Unary negation. You can also write - e instead of ~- e. Unary operator, see Ocaml_operators for more information.

val (~+) : int -> int

Unary addition. You can also write + e instead of ~+ e. Unary operator, see Ocaml_operators for more information.

since 3.12.0

val succ : int -> int

succ x is x + 1.

val pred : int -> int

pred x is x - 1.

val (+) : int -> int -> int

Integer addition. Left-associative operator, see Ocaml_operators for more information.

val (-) : int -> int -> int

Integer subtraction. Left-associative operator, , see Ocaml_operators for more information.

val (*) : int -> int -> int

Integer multiplication. Left-associative operator, see Ocaml_operators for more information.

val (/) : int -> int -> int

Integer division. Integer division rounds the real quotient of its arguments towards zero. More precisely, if x >= 0 and y > 0, x / y is the greatest integer less than or equal to the real quotient of x by y. Moreover, (- x) / y = x / (- y) = - (x / y). Left-associative operator, see Ocaml_operators for more information.

raises Division_by_zero
if the second argument is 0.

val (mod) : int -> int -> int

Integer remainder. If y is not zero, the result of x mod y satisfies the following properties: x = (x / y) * y + x mod y and abs(x mod y) <= abs(y) - 1. If y = 0, x mod y raises Division_by_zero. Note that x mod y is negative only if x < 0. Left-associative operator, see Ocaml_operators for more information.

raises Division_by_zero
if y is zero.

val abs : int -> int

Return the absolute value of the argument. Note that this may be negative if the argument is min_int.

val max_int : int

The greatest representable integer.

val min_int : int

The smallest representable integer.

Bitwise operations

val (land) : int -> int -> int

Bitwise logical and. Left-associative operator, see Ocaml_operators for more information.

val (lor) : int -> int -> int

Bitwise logical or. Left-associative operator, see Ocaml_operators for more information.

val (lxor) : int -> int -> int

Bitwise logical exclusive or. Left-associative operator, see Ocaml_operators for more information.

val lnot : int -> int

Bitwise logical negation.

val (lsl) : int -> int -> int

n lsl m shifts n to the left by m bits. The result is unspecified if m < 0 or m > Sys.int_size. Right-associative operator, see Ocaml_operators for more information.

val (lsr) : int -> int -> int

n lsr m shifts n to the right by m bits. This is a logical shift: zeroes are inserted regardless of the sign of n. The result is unspecified if m < 0 or m > Sys.int_size. Right-associative operator, see Ocaml_operators for more information.

val (asr) : int -> int -> int

n asr m shifts n to the right by m bits. This is an arithmetic shift: the sign bit of n is replicated. The result is unspecified if m < 0 or m > Sys.int_size. Right-associative operator, see Ocaml_operators for more information.

Floating-point arithmetic

OCaml's floating-point numbers follow the IEEE 754 standard, using double precision (64 bits) numbers. Floating-point operations never raise an exception on overflow, underflow, division by zero, etc. Instead, special IEEE numbers are returned as appropriate, such as infinity for 1.0 /. 0.0, neg_infinity for -1.0 /. 0.0, and nan ('not a number') for 0.0 /. 0.0. These special numbers then propagate through floating-point computations as expected: for instance, 1.0 /. infinity is 0.0, basic arithmetic operations (+., -., *., /.) with nan as an argument return nan, ...

val (~-.) : float -> float

Unary negation. You can also write -. e instead of ~-. e. Unary operator, see Ocaml_operators for more information.

val (~+.) : float -> float

Unary addition. You can also write +. e instead of ~+. e. Unary operator, see Ocaml_operators for more information.

since 3.12.0

val (+.) : float -> float -> float

Floating-point addition. Left-associative operator, see Ocaml_operators for more information.

val (-.) : float -> float -> float

Floating-point subtraction. Left-associative operator, see Ocaml_operators for more information.

val (*.) : float -> float -> float

Floating-point multiplication. Left-associative operator, see Ocaml_operators for more information.

val (/.) : float -> float -> float

Floating-point division. Left-associative operator, see Ocaml_operators for more information.

val (**) : float -> float -> float

Exponentiation. Right-associative operator, see Ocaml_operators for more information.

val sqrt : float -> float

Square root.

val exp : float -> float

Exponential.

val log : float -> float

Natural logarithm.

val log10 : float -> float

Base 10 logarithm.

val expm1 : float -> float

expm1 x computes exp x -. 1.0, giving numerically-accurate results even if x is close to 0.0.

since 3.12.0

val log1p : float -> float

log1p x computes log(1.0 +. x) (natural logarithm), giving numerically-accurate results even if x is close to 0.0.

since 3.12.0

val cos : float -> float

Cosine. Argument is in radians.

val sin : float -> float

Sine. Argument is in radians.

val tan : float -> float

Tangent. Argument is in radians.

val acos : float -> float

Arc cosine. The argument must fall within the range [-1.0, 1.0]. Result is in radians and is between 0.0 and pi.

val asin : float -> float

Arc sine. The argument must fall within the range [-1.0, 1.0]. Result is in radians and is between -pi/2 and pi/2.

val atan : float -> float

Arc tangent. Result is in radians and is between -pi/2 and pi/2.

val atan2 : float -> float -> float

atan2 y x returns the arc tangent of y /. x. The signs of x and y are used to determine the quadrant of the result. Result is in radians and is between -pi and pi.

val hypot : float -> float -> float

hypot x y returns sqrt(x *. x + y *. y), that is, the length of the hypotenuse of a right-angled triangle with sides of length x and y, or, equivalently, the distance of the point (x,y) to origin. If one of x or y is infinite, returns infinity even if the other is nan.

since 4.00.0

val cosh : float -> float

Hyperbolic cosine. Argument is in radians.

val sinh : float -> float

Hyperbolic sine. Argument is in radians.

val tanh : float -> float

Hyperbolic tangent. Argument is in radians.

val ceil : float -> float

Round above to an integer value. ceil f returns the least integer value greater than or equal to f. The result is returned as a float.

val floor : float -> float

Round below to an integer value. floor f returns the greatest integer value less than or equal to f. The result is returned as a float.

val abs_float : float -> float

abs_float f returns the absolute value of f.

val copysign : float -> float -> float

copysign x y returns a float whose absolute value is that of x and whose sign is that of y. If x is nan, returns nan. If y is nan, returns either x or -. x, but it is not specified which.

since 4.00.0

val mod_float : float -> float -> float

mod_float a b returns the remainder of a with respect to b. The returned value is a -. n *. b, where n is the quotient a /. b rounded towards zero to an integer.

val frexp : float -> float * int

frexp f returns the pair of the significant and the exponent of f. When f is zero, the significant x and the exponent n of f are equal to zero. When f is non-zero, they are defined by f = x *. 2 ** n and 0.5 <= x < 1.0.

val ldexp : float -> int -> float

ldexp x n returns x *. 2 ** n.

val modf : float -> float * float

modf f returns the pair of the fractional and integral part of f.

val float : int -> float

Same as Stdlib.float_of_int.

val float_of_int : int -> float

Convert an integer to floating-point.

val truncate : float -> int

Same as Stdlib.int_of_float.

val int_of_float : float -> int

Truncate the given floating-point number to an integer. The result is unspecified if the argument is nan or falls outside the range of representable integers.

val infinity : float

Positive infinity.

val neg_infinity : float

Negative infinity.

val nan : float

A special floating-point value denoting the result of an undefined operation such as 0.0 /. 0.0. Stands for 'not a number'. Any floating-point operation with nan as argument returns nan as result. As for floating-point comparisons, =, <, <=, > and >= return false and <> returns true if one or both of their arguments is nan.

val max_float : float

The largest positive finite value of type float.

val min_float : float

The smallest positive, non-zero, non-denormalized value of type float.

val epsilon_float : float

The difference between 1.0 and the smallest exactly representable floating-point number greater than 1.0.

type fpclass =

`\| FP_normal`	(* Normal number, none of the below *)
`\| FP_subnormal`	(* Number very close to 0.0, has reduced precision *)
`\| FP_zero`	(* Number is 0.0 or -0.0 *)
`\| FP_infinite`	(* Number is positive or negative infinity *)
`\| FP_nan`	(* Not a number: result of an undefined operation *)

The five classes of floating-point numbers, as determined by the Stdlib.classify_float function.

val classify_float : float -> fpclass

Return the class of the given floating-point number: normal, subnormal, zero, infinite, or not a number.

String operations

More string operations are provided in module String.

val (^) : string -> string -> string

String concatenation. Right-associative operator, see Ocaml_operators for more information.

Character operations

More character operations are provided in module Char.

val int_of_char : char -> int

Return the ASCII code of the argument.

val char_of_int : int -> char

Return the character with the given ASCII code.

raises Invalid_argument
if the argument is outside the range 0--255.

Unit operations

val ignore : 'a -> unit

Discard the value of its argument and return (). For instance, ignore(f x) discards the result of the side-effecting function f. It is equivalent to f x; (), except that the latter may generate a compiler warning; writing ignore(f x) instead avoids the warning.

String conversion functions

val string_of_bool : bool -> string

Return the string representation of a boolean. As the returned values may be shared, the user should not modify them directly.

val bool_of_string_opt : string -> bool option

Convert the given string to a boolean.

Return None if the string is not "true" or "false".

since 4.05

val bool_of_string : string -> bool

Same as Stdlib.bool_of_string_opt, but raise Invalid_argument "bool_of_string" instead of returning None.

val string_of_int : int -> string

Return the string representation of an integer, in decimal.

val int_of_string_opt : string -> int option

Convert the given string to an integer. The string is read in decimal (by default, or if the string begins with 0u), in hexadecimal (if it begins with 0x or 0X), in octal (if it begins with 0o or 0O), or in binary (if it begins with 0b or 0B).

The 0u prefix reads the input as an unsigned integer in the range [0, 2*max_int+1]. If the input exceeds max_int it is converted to the signed integer min_int + input - max_int - 1.

The _ (underscore) character can appear anywhere in the string and is ignored.

Return None if the given string is not a valid representation of an integer, or if the integer represented exceeds the range of integers representable in type int.

since 4.05

val int_of_string : string -> int

Same as Stdlib.int_of_string_opt, but raise Failure "int_of_string" instead of returning None.

val string_of_float : float -> string

Return the string representation of a floating-point number.

val float_of_string_opt : string -> float option

Convert the given string to a float. The string is read in decimal (by default) or in hexadecimal (marked by 0x or 0X).

The format of decimal floating-point numbers is [-] dd.ddd (e|E) [+|-] dd , where d stands for a decimal digit.

The format of hexadecimal floating-point numbers is [-] 0(x|X) hh.hhh (p|P) [+|-] dd , where h stands for an hexadecimal digit and d for a decimal digit.

In both cases, at least one of the integer and fractional parts must be given; the exponent part is optional.

The _ (underscore) character can appear anywhere in the string and is ignored.

Depending on the execution platforms, other representations of floating-point numbers can be accepted, but should not be relied upon.

Return None if the given string is not a valid representation of a float.

since 4.05

val float_of_string : string -> float

Same as Stdlib.float_of_string_opt, but raise Failure "float_of_string" instead of returning None.

Pair operations

val fst : ('a * 'b) -> 'a

Return the first component of a pair.

val snd : ('a * 'b) -> 'b

Return the second component of a pair.

List operations

More list operations are provided in module List.

val (@) : 'a list -> 'a list -> 'a list

List concatenation. Not tail-recursive (length of the first argument). Right-associative operator, see Ocaml_operators for more information.

Input/output

Note: all input/output functions can raise Sys_error when the system calls they invoke fail.

type in_channel

The type of input channel.

type out_channel

The type of output channel.

val stdin : in_channel

The standard input for the process.

val stdout : out_channel

The standard output for the process.

val stderr : out_channel

The standard error output for the process.

Output functions on standard output

val print_char : char -> unit

Print a character on standard output.

val print_string : string -> unit

Print a string on standard output.

val print_bytes : bytes -> unit

Print a byte sequence on standard output.

since 4.02.0

val print_int : int -> unit

Print an integer, in decimal, on standard output.

val print_float : float -> unit

Print a floating-point number, in decimal, on standard output.

val print_endline : string -> unit

Print a string, followed by a newline character, on standard output and flush standard output.

val print_newline : unit -> unit

Print a newline character on standard output, and flush standard output. This can be used to simulate line buffering of standard output.

Output functions on standard error

val prerr_char : char -> unit

Print a character on standard error.

val prerr_string : string -> unit

Print a string on standard error.

val prerr_bytes : bytes -> unit

Print a byte sequence on standard error.

since 4.02.0

val prerr_int : int -> unit

Print an integer, in decimal, on standard error.

val prerr_float : float -> unit

Print a floating-point number, in decimal, on standard error.

val prerr_endline : string -> unit

Print a string, followed by a newline character on standard error and flush standard error.

val prerr_newline : unit -> unit

Print a newline character on standard error, and flush standard error.

Input functions on standard input

val read_line : unit -> string

Flush standard output, then read characters from standard input until a newline character is encountered. Return the string of all characters read, without the newline character at the end.

val read_int_opt : unit -> int option

Flush standard output, then read one line from standard input and convert it to an integer.

Return None if the line read is not a valid representation of an integer.

since 4.05

val read_int : unit -> int

Same as Stdlib.read_int_opt, but raise Failure "int_of_string" instead of returning None.

val read_float_opt : unit -> float option

Flush standard output, then read one line from standard input and convert it to a floating-point number.

Return None if the line read is not a valid representation of a floating-point number.

since 4.05.0

val read_float : unit -> float

Same as Stdlib.read_float_opt, but raise Failure "float_of_string" instead of returning None.

General output functions

type open_flag =

`\| Open_rdonly`	(* open for reading. *)
`\| Open_wronly`	(* open for writing. *)
`\| Open_append`	(* open for appending: always write at end of file. *)
`\| Open_creat`	(* create the file if it does not exist. *)
`\| Open_trunc`	(* empty the file if it already exists. *)
`\| Open_excl`	(* fail if Open_creat and the file already exists. *)
`\| Open_binary`	(* open in binary mode (no conversion). *)
`\| Open_text`	(* open in text mode (may perform conversions). *)
`\| Open_nonblock`	(* open in non-blocking mode. *)

Opening modes for Stdlib.open_out_gen and Stdlib.open_in_gen.

val open_out : string -> out_channel

Open the named file for writing, and return a new output channel on that file, positioned at the beginning of the file. The file is truncated to zero length if it already exists. It is created if it does not already exists.

val open_out_bin : string -> out_channel

Same as Stdlib.open_out, but the file is opened in binary mode, so that no translation takes place during writes. On operating systems that do not distinguish between text mode and binary mode, this function behaves like Stdlib.open_out.

val open_out_gen : open_flag list -> int -> string -> out_channel

open_out_gen mode perm filename opens the named file for writing, as described above. The extra argument mode specifies the opening mode. The extra argument perm specifies the file permissions, in case the file must be created. Stdlib.open_out and Stdlib.open_out_bin are special cases of this function.

val flush : out_channel -> unit

Flush the buffer associated with the given output channel, performing all pending writes on that channel. Interactive programs must be careful about flushing standard output and standard error at the right time.

val flush_all : unit -> unit

Flush all open output channels; ignore errors.

val output_char : out_channel -> char -> unit

Write the character on the given output channel.

val output_string : out_channel -> string -> unit

Write the string on the given output channel.

val output_bytes : out_channel -> bytes -> unit

Write the byte sequence on the given output channel.

since 4.02.0

val output : out_channel -> bytes -> int -> int -> unit

output oc buf pos len writes len characters from byte sequence buf, starting at offset pos, to the given output channel oc.

raises Invalid_argument
if pos and len do not designate a valid range of buf.

val output_substring : out_channel -> string -> int -> int -> unit

Same as output but take a string as argument instead of a byte sequence.

since 4.02.0

val output_byte : out_channel -> int -> unit

Write one 8-bit integer (as the single character with that code) on the given output channel. The given integer is taken modulo 256.

val output_binary_int : out_channel -> int -> unit

Write one integer in binary format (4 bytes, big-endian) on the given output channel. The given integer is taken modulo 2³². The only reliable way to read it back is through the Stdlib.input_binary_int function. The format is compatible across all machines for a given version of OCaml.

val output_value : out_channel -> 'a -> unit

Write the representation of a structured value of any type to a channel. Circularities and sharing inside the value are detected and preserved. The object can be read back, by the function Stdlib.input_value. See the description of module Marshal for more information. Stdlib.output_value is equivalent to Marshal.to_channel with an empty list of flags.

val seek_out : out_channel -> int -> unit

seek_out chan pos sets the current writing position to pos for channel chan. This works only for regular files. On files of other kinds (such as terminals, pipes and sockets), the behavior is unspecified.

val pos_out : out_channel -> int

Return the current writing position for the given channel. Does not work on channels opened with the Open_append flag (returns unspecified results). For files opened in text mode under Windows, the returned position is approximate (owing to end-of-line conversion); in particular, saving the current position with pos_out, then going back to this position using seek_out will not work. For this programming idiom to work reliably and portably, the file must be opened in binary mode.

val out_channel_length : out_channel -> int

Return the size (number of characters) of the regular file on which the given channel is opened. If the channel is opened on a file that is not a regular file, the result is meaningless.

val close_out : out_channel -> unit

Close the given channel, flushing all buffered write operations. Output functions raise a Sys_error exception when they are applied to a closed output channel, except close_out and flush, which do nothing when applied to an already closed channel. Note that close_out may raise Sys_error if the operating system signals an error when flushing or closing.

val close_out_noerr : out_channel -> unit

Same as close_out, but ignore all errors.

val set_binary_mode_out : out_channel -> bool -> unit

set_binary_mode_out oc true sets the channel oc to binary mode: no translations take place during output. set_binary_mode_out oc false sets the channel oc to text mode: depending on the operating system, some translations may take place during output. For instance, under Windows, end-of-lines will be translated from \n to \r\n. This function has no effect under operating systems that do not distinguish between text mode and binary mode.

General input functions

val open_in : string -> in_channel

Open the named file for reading, and return a new input channel on that file, positioned at the beginning of the file.

val open_in_bin : string -> in_channel

Same as Stdlib.open_in, but the file is opened in binary mode, so that no translation takes place during reads. On operating systems that do not distinguish between text mode and binary mode, this function behaves like Stdlib.open_in.

val open_in_gen : open_flag list -> int -> string -> in_channel

open_in_gen mode perm filename opens the named file for reading, as described above. The extra arguments mode and perm specify the opening mode and file permissions. Stdlib.open_in and Stdlib.open_in_bin are special cases of this function.

val input_char : in_channel -> char

Read one character from the given input channel.

raises End_of_file
if there are no more characters to read.

val input_line : in_channel -> string

Read characters from the given input channel, until a newline character is encountered. Return the string of all characters read, without the newline character at the end.

raises End_of_file
if the end of the file is reached at the beginning of line.

val input : in_channel -> bytes -> int -> int -> int

input ic buf pos len reads up to len characters from the given channel ic, storing them in byte sequence buf, starting at character number pos. It returns the actual number of characters read, between 0 and len (inclusive). A return value of 0 means that the end of file was reached. A return value between 0 and len exclusive means that not all requested len characters were read, either because no more characters were available at that time, or because the implementation found it convenient to do a partial read; input must be called again to read the remaining characters, if desired. (See also Stdlib.really_input for reading exactly len characters.) Exception Invalid_argument "input" is raised if pos and len do not designate a valid range of buf.

val really_input : in_channel -> bytes -> int -> int -> unit

really_input ic buf pos len reads len characters from channel ic, storing them in byte sequence buf, starting at character number pos.

raises End_of_file
if the end of file is reached before len characters have been read.

raises Invalid_argument
if pos and len do not designate a valid range of buf.

val really_input_string : in_channel -> int -> string

really_input_string ic len reads len characters from channel ic and returns them in a new string.

raises End_of_file
if the end of file is reached before len characters have been read.

since 4.02.0

val input_byte : in_channel -> int

Same as Stdlib.input_char, but return the 8-bit integer representing the character.

raises End_of_file
if an end of file was reached.

val input_binary_int : in_channel -> int

Read an integer encoded in binary format (4 bytes, big-endian) from the given input channel. See Stdlib.output_binary_int.

raises End_of_file
if an end of file was reached while reading the integer.

val input_value : in_channel -> 'a

Read the representation of a structured value, as produced by Stdlib.output_value, and return the corresponding value. This function is identical to Marshal.from_channel; see the description of module Marshal for more information, in particular concerning the lack of type safety.

val seek_in : in_channel -> int -> unit

seek_in chan pos sets the current reading position to pos for channel chan. This works only for regular files. On files of other kinds, the behavior is unspecified.

val pos_in : in_channel -> int

Return the current reading position for the given channel. For files opened in text mode under Windows, the returned position is approximate (owing to end-of-line conversion); in particular, saving the current position with pos_in, then going back to this position using seek_in will not work. For this programming idiom to work reliably and portably, the file must be opened in binary mode.

val in_channel_length : in_channel -> int

Return the size (number of characters) of the regular file on which the given channel is opened. If the channel is opened on a file that is not a regular file, the result is meaningless. The returned size does not take into account the end-of-line translations that can be performed when reading from a channel opened in text mode.

val close_in : in_channel -> unit

Close the given channel. Input functions raise a Sys_error exception when they are applied to a closed input channel, except close_in, which does nothing when applied to an already closed channel.

val close_in_noerr : in_channel -> unit

Same as close_in, but ignore all errors.

val set_binary_mode_in : in_channel -> bool -> unit

set_binary_mode_in ic true sets the channel ic to binary mode: no translations take place during input. set_binary_mode_out ic false sets the channel ic to text mode: depending on the operating system, some translations may take place during input. For instance, under Windows, end-of-lines will be translated from \r\n to \n. This function has no effect under operating systems that do not distinguish between text mode and binary mode.

Operations on large files

module LargeFile : sig ... end

Operations on large files. This sub-module provides 64-bit variants of the channel functions that manipulate file positions and file sizes. By representing positions and sizes by 64-bit integers (type int64) instead of regular integers (type int), these alternate functions allow operating on files whose sizes are greater than max_int.

References

type 'a ref = {

mutable contents : 'a;

}

The type of references (mutable indirection cells) containing a value of type 'a.

val ref : 'a -> 'a ref

Return a fresh reference containing the given value.

val (!) : 'a ref -> 'a

!r returns the current contents of reference r. Equivalent to fun r -> r.contents. Unary operator, see Ocaml_operators for more information.

val (:=) : 'a ref -> 'a -> unit

r := a stores the value of a in reference r. Equivalent to fun r v -> r.contents <- v. Right-associative operator, see Ocaml_operators for more information.

val incr : int ref -> unit

Increment the integer contained in the given reference. Equivalent to fun r -> r := succ !r.

val decr : int ref -> unit

Decrement the integer contained in the given reference. Equivalent to fun r -> r := pred !r.

Result type

type ('a, 'b) result =

| Ok of 'a

| Error of 'b

since 4.03.0

Operations on format strings

Format strings are character strings with special lexical conventions that defines the functionality of formatted input/output functions. Format strings are used to read data with formatted input functions from module Scanf and to print data with formatted output functions from modules Printf and Format.

Format strings are made of three kinds of entities:

conversions specifications, introduced by the special character '%' followed by one or more characters specifying what kind of argument to read or print,
formatting indications, introduced by the special character '@' followed by one or more characters specifying how to read or print the argument,
plain characters that are regular characters with usual lexical conventions. Plain characters specify string literals to be read in the input or printed in the output.

There is an additional lexical rule to escape the special characters '%' and '@' in format strings: if a special character follows a '%' character, it is treated as a plain character. In other words, "%%" is considered as a plain '%' and "%@" as a plain '@'.

For more information about conversion specifications and formatting indications available, read the documentation of modules Scanf, Printf and Format.

Format strings have a general and highly polymorphic type ('a, 'b, 'c, 'd, 'e, 'f) format6. The two simplified types, format and format4 below are included for backward compatibility with earlier releases of OCaml.

The meaning of format string type parameters is as follows:

'a is the type of the parameters of the format for formatted output functions (printf-style functions); 'a is the type of the values read by the format for formatted input functions (scanf-style functions).

'b is the type of input source for formatted input functions and the type of output target for formatted output functions. For printf-style functions from module Printf, 'b is typically out_channel; for printf-style functions from module Format, 'b is typically Format.formatter; for scanf-style functions from module Scanf, 'b is typically Scanf.Scanning.in_channel.

Type argument 'b is also the type of the first argument given to user's defined printing functions for %a and %t conversions, and user's defined reading functions for %r conversion.

'c is the type of the result of the %a and %t printing functions, and also the type of the argument transmitted to the first argument of kprintf-style functions or to the kscanf-style functions.

'd is the type of parameters for the scanf-style functions.

'e is the type of the receiver function for the scanf-style functions.

'f is the final result type of a formatted input/output function invocation: for the printf-style functions, it is typically unit; for the scanf-style functions, it is typically the result type of the receiver function.

type ('a, 'b, 'c, 'd, 'e, 'f) format6 =
  ( 'a, 'b, 'c, 'd, 'e, 'f ) CamlinternalFormatBasics.format6

type ('a, 'b, 'c, 'd) format4 = ( 'a, 'b, 'c, 'c, 'c, 'd ) format6

type ('a, 'b, 'c) format = ( 'a, 'b, 'c, 'c ) format4

val string_of_format : ( 'a, 'b, 'c, 'd, 'e, 'f ) format6 -> string

Converts a format string into a string.

val format_of_string : 
  ( 'a, 'b, 'c, 'd, 'e, 'f ) format6 ->
  ( 'a, 'b, 'c, 'd, 'e, 'f ) format6

format_of_string s returns a format string read from the string literal s. Note: format_of_string can not convert a string argument that is not a literal. If you need this functionality, use the more general Scanf.format_from_string function.

val (^^) : 
  ( 'a, 'b, 'c, 'd, 'e, 'f ) format6 ->
  ( 'f, 'b, 'c, 'e, 'g, 'h ) format6 ->
  ( 'a, 'b, 'c, 'd, 'g, 'h ) format6

f1 ^^ f2 catenates format strings f1 and f2. The result is a format string that behaves as the concatenation of format strings f1 and f2: in case of formatted output, it accepts arguments from f1, then arguments from f2; in case of formatted input, it returns results from f1, then results from f2. Right-associative operator, see Ocaml_operators for more information.

Program termination

val exit : int -> 'a

Terminate the process, returning the given status code to the operating system: usually 0 to indicate no errors, and a small positive integer to indicate failure. All open output channels are flushed with flush_all. An implicit exit 0 is performed each time a program terminates normally. An implicit exit 2 is performed if the program terminates early because of an uncaught exception.

val at_exit : ( unit -> unit ) -> unit

Register the given function to be called at program termination time. The functions registered with at_exit will be called when the program does any of the following:

executes Stdlib.exit
terminates, either normally or because of an uncaught exception
executes the C function caml_shutdown. The functions are called in 'last in, first out' order: the function most recently added with at_exit is called first.

Standard library modules

module Arg : sig ... end

Parsing of command line arguments.

module Array : sig ... end

Array operations.

module ArrayLabels : sig ... end

Array operations.

module Atomic : sig ... end

This module provides a purely sequential implementation of the concurrent atomic references provided by the Multicore OCaml standard library:

module Bigarray : sig ... end

Large, multi-dimensional, numerical arrays.

module Bool : sig ... end

Boolean values.

module Buffer : sig ... end

Extensible buffers.

module Bytes : sig ... end

Byte sequence operations.

module BytesLabels : sig ... end

Byte sequence operations.

module Callback : sig ... end

Registering OCaml values with the C runtime.

module Char : sig ... end

Character operations.

module Complex : sig ... end

Complex numbers.

module Digest : sig ... end

MD5 message digest.

module Either : sig ... end

Either type.

module Ephemeron : sig ... end

Ephemerons and weak hash tables.

module Filename : sig ... end

Operations on file names.

module Float : sig ... end

Floating-point arithmetic.

module Format : sig ... end

Pretty-printing.

module Fun : sig ... end

Function manipulation.

module Gc : sig ... end

Memory management control and statistics; finalised values.

module Genlex : sig ... end

A generic lexical analyzer.

module Hashtbl : sig ... end

Hash tables and hash functions.

module Int : sig ... end

Integer values.

module Int32 : sig ... end

32-bit integers.

module Int64 : sig ... end

64-bit integers.

module Lazy : sig ... end

Deferred computations.

module Lexing : sig ... end

The run-time library for lexers generated by ocamllex.

module List : sig ... end

List operations.

module ListLabels : sig ... end

List operations.

module Map : sig ... end

Association tables over ordered types.

module Marshal : sig ... end

Marshaling of data structures.

module MoreLabels : sig ... end

Extra labeled libraries.

module Nativeint : sig ... end

Processor-native integers.

module Obj : sig ... end

Operations on internal representations of values.

module Oo : sig ... end

Operations on objects

module Option : sig ... end

Option values.

module Parsing : sig ... end

The run-time library for parsers generated by ocamlyacc.

module Pervasives : sig ... end

module Printexc : sig ... end

Facilities for printing exceptions and inspecting current call stack.

module Printf : sig ... end

Formatted output functions.

module Queue : sig ... end

First-in first-out queues.

module Random : sig ... end

Pseudo-random number generators (PRNG).

module Result : sig ... end

Result values.

module Scanf : sig ... end

Formatted input functions.

module Seq : sig ... end

Functional iterators.

module Set : sig ... end

Sets over ordered types.

module Stack : sig ... end

Last-in first-out stacks.

module StdLabels : sig ... end

Standard labeled libraries.

module Stream : sig ... end

Streams and parsers.

module String : sig ... end

Strings.

module StringLabels : sig ... end

Strings.

module Sys : sig ... end

System interface.

module Uchar : sig ... end

Unicode characters.

module Unit : sig ... end

Unit values.

module Weak : sig ... end

Arrays of weak pointers and hash sets of weak pointers.