Module BatPervasives

module BatPervasives: sig .. end

val uppercase : string -> string

Return a copy of the argument, with all lowercase letters translated to uppercase, including accented letters of the ISO Latin-1 (8859-1) character set.

val lowercase : string -> string

Return a copy of the argument, with all uppercase letters translated to lowercase, including accented letters of the ISO Latin-1 (8859-1) character set.

val string_of_char : char -> string

creates a string from a char.

val dump : 'a -> string

Attempt to convert a value to a string.

Since types are lost at compile time, the representation might not match your type. For example, None will be printed 0 since they share the same runtime representation.

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

List concatenation.

val stdin : BatIO.input

Standard input, as per Unix/Windows conventions (by default, keyboard).

Use this input to read what the user is writing on the keyboard.

val stdout : unit BatIO.output

Standard output, as per Unix/Windows conventions (by default, console).

Use this output to display regular messages.

val stderr : unit BatIO.output

Standard error output, as per Unix/Windows conventions.

Use this output to display warnings and error messages.

val stdnull : unit BatIO.output

An output which discards everything written to it.

Use this output to ignore messages.

val flush_all : unit -> unit

Write all pending data to output channels, ignore all errors.

It is normally not necessary to call this function, as all pending data is written when an output channel is closed or when the program itself terminates, either normally or because of an uncaught exception. However, this function is useful for debugging, as it forces pending data to be written immediately.

val print_bool : bool -> unit

Print a boolean on standard output.

val print_guess : 'a BatIO.output -> 'b -> unit

Attempt to print the representation of a runtime value on the standard output. See remarks for BatPervasives.dump. This function is useful mostly for debugging. As a general rule, it should not be used in production code.

val print_all : BatIO.input -> unit

Print the contents of an input to the standard output.

val prerr_bool : bool -> unit

Print a boolean to stderr.

val prerr_guess : 'a -> unit

Attempt to print the representation of a runtime value on the error output. See remarks for BatPervasives.dump. This function is useful mostly for debugging.

val prerr_all : BatIO.input -> unit

Print the contents of an input to the error output.

val open_out : ?mode:BatFile.open_out_flag list ->
       ?perm:BatFile.permission -> string -> unit BatIO.output

Open the named file for writing, and return a new output channel on that file. You will need to close the file once you have finished using it.

You may use optional argument mode to decide whether the output will overwrite the contents of the file (by default) or to add things at the end of the file, whether the file should be created if it does not exist yet (the default) or not, whether this operation should proceed if the file exists already (the default) or not, whether the file should be opened as text (the default) or as binary, and whether the file should be opened for non-blocking operations.

You may use optional argument perm to specify the permissions of the file, as per Unix conventions. By default, files are created with default permissions (which depend on your setup).

Raise Sys_error if the file could not be opened.

val open_out_bin : string -> unit BatIO.output

Same as BatPervasives.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 BatPervasives.open_out without any mode or perm.

val open_out_gen : Pervasives.open_flag list -> int -> string -> unit BatIO.output

Deprecated.Use open_out instead
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.

val flush : unit BatIO.output -> unit

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

val output_char : unit BatIO.output -> char -> unit

Write the character on the given output channel.

val output_string : unit BatIO.output -> string -> unit

Write the string on the given output channel.

val output_rope : unit BatIO.output -> BatRope.t -> unit

Write the rope on the given output channel.

val output : unit BatIO.output -> string -> int -> int -> unit

output oc buf pos len writes len characters from string buf, starting at offset pos, to the given output channel oc. Raise Invalid_argument "output" if pos and len do not designate a valid substring of buf.

val output_byte : unit BatIO.output -> 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 : unit BatIO.output -> 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 Pervasives.input_binary_int function. The format is compatible across all machines for a given version of Objective Caml.

val output_value : unit BatIO.output -> '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 BatPervasives.input_value. See the description of module Marshal for more information. BatPervasives.output_value is equivalent to Marshal.output with an empty list of flags.

val close_out : unit BatIO.output -> 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 : unit BatIO.output -> unit

Same as close_out, but ignore all errors.

val open_in : ?mode:BatFile.open_in_flag list ->
       ?perm:BatFile.permission -> string -> BatIO.input

Open the named file for reading. You will need to close the file once you have finished using it.

You may use optional argument mode to decide whether the opening should fail if the file doesn't exist yet (by default) or whether the file should be created if it doesn't exist yet, whether the opening should fail if the file already exists or not (by default), whether the file should be read as binary (by default) or as text, and whether reading should be non-blocking.

You may use optional argument perm to specify the permissions of the file, should it be created, as per Unix conventions. By default, files are created with default permissions (which depend on your setup).

Raise Sys_error if the file could not be opened.

val open_in_bin : string -> BatIO.input

Same as Pervasives.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 Pervasives.open_in.

val open_in_gen : Pervasives.open_flag list -> int -> string -> BatIO.input

Deprecated.Use open_in instead
open_in 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. Pervasives.open_in and Pervasives.open_in_bin are special cases of this function.

val input_char : BatIO.input -> char

Read one character from the given input channel. Raise End_of_file if there are no more characters to read.

val input_line : BatIO.input -> 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. Raise End_of_file if the end of the file is reached at the beginning of line.

val input : BatIO.input -> string -> int -> int -> int

input ic buf pos len reads up to len characters from the given channel ic, storing them in string 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 Pervasives.really_input for reading exactly len characters.) Exception Invalid_argument "input" is raised if pos and len do not designate a valid substring of buf.

val really_input : BatIO.input -> string -> int -> int -> unit

really_input ic buf pos len reads len characters from channel ic, storing them in string buf, starting at character number pos. Raise End_of_file if the end of file is reached before len characters have been read. Raise Invalid_argument "really_input" if pos and len do not designate a valid substring of buf.

val input_byte : BatIO.input -> int

Same as Pervasives.input_char, but return the 8-bit integer representing the character. Raise End_of_file if an end of file was reached.

val input_binary_int : BatIO.input -> int

Read an integer encoded in binary format (4 bytes, big-endian) from the given input channel. See Pervasives.output_binary_int. Raise End_of_file if an end of file was reached while reading the integer.

val input_value : BatIO.input -> 'a

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

val close_in : BatIO.input -> 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. Note that close_in may raise Sys_error if the operating system signals an error.

val close_in_noerr : BatIO.input -> unit

Same as close_in, but ignore all errors.

val identity : 'a -> 'a

The identity function.

val undefined : ?message:string -> 'a -> 'b

The undefined function.

Evaluating undefined x always fails and raises an exception "Undefined". Optional argument message permits the customization of the error message.

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

Function application. x |> f is equivalent to f x.

This operator is commonly used to write a function composition by order of evaluation (the order used in object-oriented programming) rather than by inverse order (the order typically used in functional programming).

For instance, g (f x) means "apply f to x, then apply g to the result." The corresponding notation in most object-oriented programming languages would be somewhere along the lines of x.f.g (), or "starting from x, apply f, then apply g." In OCaml, operator ( |> ) this latest notation maps to x |> f |> g, or

This operator may also be useful for composing sequences of function calls without too many parenthesis.

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

Function application. f **> x is equivalent to f x.

This operators may be useful for composing sequences of function calls without too many parenthesis.

Note The name of this operator is not written in stone. It is bound to change soon.

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

Function composition. f |- g is fun x -> g (f x). This is also equivalent to applying <** twice.

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

Function composition. f -| g is fun x -> f (g x). Mathematically, this is operator o.

val flip : ('a -> 'b -> 'c) -> 'b -> 'a -> 'c

Argument flipping.

flip f x y is f y x. Don't abuse this function, it may shorten considerably your code but it also has the nasty habit of making it harder to read.

val ( *** ) : ('a -> 'b) -> ('c -> 'd) -> 'a * 'c -> 'b * 'd

Function pairing.

f *** g is fun (x,y) -> (f x, g y).

val (&&&) : ('a -> 'b) -> ('a -> 'c) -> 'a -> 'b * 'c

Applying two functions to the same argument.

f &&& g is fun x -> (f x, g x).

val first : ('a -> 'b) -> 'a * 'c -> 'b * 'c

Apply a function to the first element of a pair.

first f (x, y) is (f x, y)

val second : ('a -> 'b) -> 'c * 'a -> 'c * 'b

Apply a function to the second element of a pair.

second f (x, y) is (x, f y)

val curry : ('a * 'b -> 'c) -> 'a -> 'b -> 'c

Convert a function which accepts a pair of arguments into a function which accepts two arguments.

curry f is fun x y -> f (x,y)

val uncurry : ('a -> 'b -> 'c) -> 'a * 'b -> 'c

Convert a function which accepts a two arguments into a function which accepts a pair of arguments.

uncurry f is fun (x, y) -> f x y

val const : 'a -> 'b -> 'a

Ignore its second argument.

const x is the function which always returns x.

val unique : unit -> int

Returns an unique identifier every time it is called.

Note This is thread-safe.

val finally : (unit -> unit) -> ('a -> 'b) -> 'a -> 'b

finally fend f x calls f x and then fend() even if f x raised an exception.

val args : unit -> string BatEnum.t

An enumeration of the arguments passed to this program through the command line.

args () is given by the elements of Sys.argv, minus the first element.

val exe : string

The name of the current executable.

exe is given by the first argument of Sys.argv

val foreach : 'a BatEnum.t -> ('a -> unit) -> unit

Imperative loop on an enumeration.

foreach e f applies function f to each successive element of e. For instance, foreach (1 -- 10) print_int invokes function print_int on 1, 2, ..., 10, printing 12345678910.

Note This function is one of the many loops available on enumerations. Other commonly used loops are BatPervasives.iter (same usage scenario as foreach, but with different notations), BatPervasives.map (convert an enumeration to another enumeration) or BatPervasives.fold (flatten an enumeration by applying an operation to each element).

val iter : ('a -> unit) -> 'a BatEnum.t -> unit

Imperative loop on an enumeration. This loop is typically used to lift a function with an effect but no meaningful result and get it to work on enumerations.

If f is a function iter f is a function which behaves as f but acts upon enumerations rather than individual elements. As indicated in the type of iter, f must produce values of type unit (i.e. f has no meaningful result) the resulting function produces no meaningful result either.

In other words, iter f is a function which, when applied upon an enumeration e, calls f with each element of e in turn.

For instance, iter f (1 -- 10) invokes function f on 1, 2, ..., 10 and produces value ().

val map : ('a -> 'b) -> 'a BatEnum.t -> 'b BatEnum.t

Transformation loop on an enumeration, used to build an enumeration from another enumeration. This loop is typically used to transform an enumeration into another enumeration with the same number of elements, in the same order.

If f is a function, map f e is a function which behaves as f but acts upon enumerations rather than individual elements -- and builds a new enumeration from the results of each application.

In other words, map f is a function which, when applied upon an enumeration containing elements e1, e2, ..., produces enumeration f e1, f e2, ...

For instance, if odd is the function which returns true when applied to an odd number or false when applied to an even number, map odd (1 -- 10) produces enumeration true, false, true, ..., false.

Similarly, if square is the function fun x -> x * x, map square (1 -- 10) produces the enumeration of the square numbers of all numbers between 1 and 10.

val reduce : ('a -> 'a -> 'a) -> 'a BatEnum.t -> 'a

Transformation loop on an enumeration, used to build a single value from an enumeration.

If f is a function and e is an enumeration, reduce f e applies function f to the first two elements of e, then to the result of this expression and to the third element of e, then to the result of this new expression and to the fourth element of e...

In other words, fold f e returns a_1 if e contains only one element, otherwise f (... (f (f a1) a2) ...) aN where a1..N are the elements of e.

val fold : ('a -> 'b -> 'a) -> 'a -> 'b BatEnum.t -> 'a

Transformation loop on an enumeration, used to build a single value from an enumeration. This is the most powerful general-purpose loop and also the most complex.

If f is a function, fold f v e applies f v to the first element of e, then, calling acc_1 the result of this operation, applies f acc_1 to the second element of e, then, calling acc_2 the result of this operation, applies f acc_2 to the third element of e...

In other words, fold f v e returns v if e is empty, otherwise f (... (f (f v a1) a2) ...) aN where a1..N are the elements of e.

For instance, if add is the function fun x y -> x + y, fold add 0 is the function which computes the sum of the elements of an enumeration. Therefore, fold add 0 (1 -- 10) produces result 55.

val scanl : ('a -> 'b -> 'a) -> 'a -> 'b BatEnum.t -> 'a BatEnum.t

Functional loop on an enumeration, used to build an enumeration from both an enumeration and an initial value. This function may be seen as a variant of BatPervasives.fold which returns not only the final result of BatPervasives.fold but the enumeration of all the intermediate results of BatPervasives.fold.

If f is a function, scanl f v e is applies f v to the first element of e, then, calling acc_1 the result of this operation, applies f acc_1 to the second element of e, then, calling acc_2 the result of this operation, applies f acc_2 to the third element of e...

For instance, if add is the function fun x y -> x + y, scanl add 0 is the function which computes the sum of the elements of an enumeration. Therefore, scanl add 0 (1 -- 10) produces result the enumeration with elements 0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55.

val (/@) : 'a BatEnum.t -> ('a -> 'b) -> 'b BatEnum.t

val (@/) : ('a -> 'b) -> 'a BatEnum.t -> 'b BatEnum.t

Mapping operators.

These operators have the same meaning as function BatPervasives.map but are sometimes more readable than this function, when chaining several transformations in a row.

val exists : ('a -> bool) -> 'a BatEnum.t -> bool

exists f e returns true if there is some x in e such that f x

val for_all : ('a -> bool) -> 'a BatEnum.t -> bool

exists f e returns true if for every x in e, f x is true

val find : ('a -> bool) -> 'a BatEnum.t -> 'a

find f e returns the first element x of e such that f x returns true, consuming the enumeration up to and including the found element, or, raises Not_found if no such element exists in the enumeration, consuming the whole enumeration in the search.

Since find consumes a prefix of the enumeration, it can be used several times on the same enumeration to find the next element.

val peek : 'a BatEnum.t -> 'a option

peek e returns None if e is empty or Some x where x is the next element of e. The element is not removed from the enumeration.

val get : 'a BatEnum.t -> 'a option

get e returns None if e is empty or Some x where x is the next element of e, in which case the element is removed from the enumeration.

val push : 'a BatEnum.t -> 'a -> unit

push e x will add x at the beginning of e.

val junk : 'a BatEnum.t -> unit

junk e removes the first element from the enumeration, if any.

val filter : ('a -> bool) -> 'a BatEnum.t -> 'a BatEnum.t

filter f e returns an enumeration over all elements x of e such as f x returns true.

val (//) : 'a BatEnum.t -> ('a -> bool) -> 'a BatEnum.t

Filtering (pronounce this operator name "such that").

For instance, (1 -- 37) // odd is the enumeration of all odd numbers between 1 and 37.

val concat : 'a BatEnum.t BatEnum.t -> 'a BatEnum.t

concat e returns an enumeration over all elements of all enumerations of e.

val (--) : int -> int -> int BatEnum.t

Enumerate numbers.

5 -- 10 is the enumeration 5,6,7,8,9,10. 10 -- 5 is the empty enumeration

val (--^) : int -> int -> int BatEnum.t

Enumerate numbers, without the right endpoint

5 -- 10 is the enumeration 5,6,7,8,9.

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

(a, step) --. b) creates a float enumeration from a to b with an increment of step between elements.

(5.0, 1.0) --. 10.0 is the enumeration 5.0,6.0,7.0,8.0,9.0,10.0. (10.0, -1.0) --. 5.0 is the enumeration 10.0,9.0,8.0,7.0,6.0,5.0. (10.0, 1.0) --. 1.0 is the empty enumeration.

val (---) : int -> int -> int BatEnum.t

As --, but accepts enumerations in reverse order.

5 --- 10 is the enumeration 5,6,7,8,9,10. 10 --- 5 is the enumeration 10,9,8,7,6,5.

val (--~) : char -> char -> char BatEnum.t

As ( -- ), but for characters.

val print : ?first:string ->
       ?last:string ->
       ?sep:string ->
       ('a BatInnerIO.output -> 'b -> unit) ->
       'a BatInnerIO.output -> 'b BatEnum.t -> unit

Print and consume the contents of an enumeration.

type ('a, 'b) result = ('a, 'b) BatStd.result = 

val lock : BatConcurrent.lock Pervasives.ref

A lock used to synchronize internal operations.

By default, this is Concurrent.nolock. However, if you're using a version of Batteries compiled in threaded mode, this uses Mutex. If you're attempting to use Batteries with another concurrency model, set the lock appropriately.