Module Stdlib

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 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 raised by library functions to signal that the given arguments do not make sense.

Exception raised by library functions to signal that they are undefined on the given arguments.

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

Exception raised by the garbage collector when there is insufficient memory to complete the computation.

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. (Not fully implemented by the native-code compiler; see section 11.4.)

Exception raised by the input/output functions to report an operating system error.

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

Exception raised by division and remainder operations when their second argument is null. (Not fully implemented by the native-code compiler; see section 11.4.)

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

Raise the given exception value

Raise exception Invalid_argument with the given string.

Raise exception Failure with the given string.

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

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 may raise Invalid_argument. Equality between cyclic data structures may not terminate.

Negation of Stdlib.(=).

See Stdlib.(>=).

See Stdlib.(>=).

See Stdlib.(>=).

Structural ordering functions. These functions coincide with the usual orderings over integers, characters, strings 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 may raise Invalid_argument. Comparison between cyclic structures may not terminate.

compare x y returns 0 if x=y, a negative integer if x<y, and a positive integer if x>y. The same restrictions as for = apply. compare can be used as the comparison function required by the Set.Make and Map.Make functors.

Return the smaller of the two arguments.

Return the greater of the two arguments.

e1 == e2 tests for physical equality of e1 and e2. On integers and characters, physical equality is identical to structural equality. On mutable structures, e1 == e2 is true if and only if physical modification of e1 also affects e2. On non-mutable structures, the behavior of (==) is implementation-dependent; however, it is guaranteed that e1 == e2 implies e1 = e2.

Negation of Stdlib.(==).

The boolean negation.

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.

The boolean ``or''. Evaluation is sequential, left-to-right: in e1 or e2, e1 is evaluated first, and if it returns true, e2 is not evaluated at all.

Unary negation. You can also write -e instead of ~-e.

succ x is x+1.

pred x is x-1.

Integer addition.

Integer subtraction.

Integer multiplication.

Integer division. Raise Division_by_zero if the second argument is 0. 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).

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. Notice that x mod y is negative if and only if x < 0.

Return the absolute value of the argument.

The greatest representable integer.

The smallest representable integer.

Bitwise logical and.

Bitwise logical or.

Bitwise logical exclusive or.

Bitwise logical negation.

n lsl m shifts n to the left by m bits. The result is unspecified if m < 0 or m >= bitsize, where bitsize is 32 on a 32-bit platform and 64 on a 64-bit platform.

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 >= bitsize.

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 >= bitsize.

Unary negation. You can also write -.e instead of ~-.e.

Floating-point addition

Floating-point subtraction

Floating-point multiplication

Floating-point division.

Exponentiation

Square root

Exponential.

Natural logarithm.

Base 10 logarithm.

See Stdlib.atan2.

See Stdlib.atan2.

See Stdlib.atan2.

See Stdlib.atan2.

See Stdlib.atan2.

See Stdlib.atan2.

The usual trigonometric functions.

See Stdlib.tanh.

See Stdlib.tanh.

The usual hyperbolic trigonometric functions.

See Stdlib.floor.

Round the given float to an integer value. floor f returns the greatest integer value less than or equal to f. ceil f returns the least integer value greater than or equal to f.

Return the absolute value of the argument.

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.

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.

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

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

Same as Stdlib.float_of_int.

Convert an integer to floating-point.

Same as Stdlib.int_of_float.

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

Positive infinity.

Negative infinity.

A special floating-point value denoting the result of an undefined operation such as 0.0 /. 0.0. Stands for ``not a number''.

The largest positive finite value of type float.

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

The smallest positive float x such that 1.0 +. x <> 1.0.

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

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

String concatenation.

Return the ASCII code of the argument.

Return the character with the given ASCII code. Raise Invalid_argument "char_of_int" if the argument is outside the range 0--255.

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.

Return the string representation of a boolean.

Convert the given string to a boolean. Raise Invalid_argument "bool_of_string" if the string is not "true" or "false".

Return the string representation of an integer, in decimal.

Convert the given string to an integer. The string is read in decimal (by default) or in hexadecimal (if it begins with 0x or 0X), octal (if it begins with 0o or 0O), or binary (if it begins with 0b or 0B). Raise Failure "int_of_string" if the given string is not a valid representation of an integer.

Return the string representation of a floating-point number.

Convert the given string to a float. Raise Failure "float_of_string" if the given string is not a valid representation of a float.

Return the first component of a pair.

Return the second component of a pair.

List concatenation.

The type of input channel.

The type of output channel.

The standard input for the process.

The standard output for the process.

The standard error ouput for the process.

Print a character on standard output.

Print a string on standard output.

Print an integer, in decimal, on standard output.

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

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

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

Print a character on standard error.

Print a string on standard error.

Print an integer, in decimal, on standard error.

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

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

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

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.

Flush standard output, then read one line from standard input and convert it to an integer. Raise Failure "int_of_string" if the line read is not a valid representation of an integer.

Flush standard output, then read one line from standard input and convert it to a floating-point number. The result is unspecified if the line read is not a valid representation of a floating-point number.

Opening modes for Stdlib.open_out_gen and Stdlib.open_in_gen.

Open the named file for writing, and return a new output channel on that file, positionned 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. Raise Sys_error if the file could not be opened.

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.

Open the named file for writing, as above. The extra argument mode specify 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.

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.

Flush all open output channels; ignore errors.

Write the character on the given output channel.

Write the string on the given output channel.

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.

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

Write one integer in binary format on the given output channel. 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 Objective Caml.

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.

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.

Return the current writing position for the given channel.

Return the total length (number of characters) of the given channel. This works only for regular files. On files of other kinds, the result is meaningless.

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.

Same as close_out, but ignore all errors.

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.

Open the named file for reading, and return a new input channel on that file, positionned at the beginning of the file. Raise Sys_error if the file could not be opened.

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.

Open the named file for reading, as 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.

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

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.

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 Stdlib.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.

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.

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

Read an integer encoded in binary format from the given input channel. See Stdlib.output_binary_int. Raise End_of_file if an end of file was reached while reading the integer.

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.

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.

Return the current reading position for the given channel.

Return the total length (number of characters) of the given channel. This works only for regular files. On files of other kinds, the result is meaningless.

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.

Same as close_in, but ignore all errors.

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.

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

Return a fresh reference containing the given value.

!r returns the current contents of reference r. Equivalent to fun r -> r.contents.

r := a stores the value of a in reference r. Equivalent to fun r v -> r.contents <- v.

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

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

Simplified type for format strings, included for backward compatibility with earlier releases of Objective Caml. 'a is the type of the parameters of the format, 'c is the result type for the "printf"-style function, and 'b is the type of the first argument given to %a and %t printing functions.

Converts a format string into a string.

format_of_string s returns a format string read from the string literal s.

f1 ^^ f2 catenates formats f1 and f2. The result is a format that accepts arguments from f1, then arguments from f2.

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.

Register the given function to be called at program termination time. The functions registered with at_exit will be called when the program executes Stdlib.exit, or terminates, either normally or because of an uncaught exception. The functions are called in ``last in, first out'' order: the function most recently added with at_exit is called first.