NAME
ocaml - The Objective Caml interactive toplevel
SYNOPSIS
ocaml [ options ] [ object-files ] [ script-file ]
DESCRIPTION
The ocaml(1) command is the toplevel system for Objective Caml, that
permits interactive use of the Objective Caml system through a read-
eval-print loop. In this mode, the system repeatedly reads Caml phrases
from the input, then typechecks, compiles and evaluates them, then
prints the inferred type and result value, if any. The system prints a
# (sharp) prompt before reading each phrase.
A toplevel phrase can span several lines. It is terminated by ;; (a
double-semicolon). The syntax of toplevel phrases is as follows.
The toplevel system is started by the command ocaml(1). Phrases are
read on standard input, results are printed on standard output, errors
on standard error. End-of-file on standard input terminates ocaml(1).
If one or more object-files (ending in .cmo or .cma) are given, they
are loaded silently before starting the toplevel.
If a script-file is given, phrases are read silently from the file,
errors printed on standard error. ocaml(1) exits after the execution
of the last phrase.
OPTIONS
The following command-line options are recognized by ocaml(1).
-I directory
Add the given directory to the list of directories searched for
source and compiled files. By default, the current directory is
searched first, then the standard library directory. Directories
added with -I are searched after the current directory, in the
order in which they were given on the command line, but before
the standard library directory.
If the given directory starts with +, it is taken relative to
the standard library directory. For instance, -I +labltk adds
the subdirectory labltk of the standard library to the search
path.
Directories can also be added to the search path once the
toplevel is running with the #directory directive.
-init file
Load the given file instead of the default initialization file.
The default file is .ocamlinit in the current directory if it
exists, otherwise .ocamlinit in the user’s home directory.
-labels
Labels are not ignored in types, labels may be used in
applications, and labelled parameters can be given in any order.
This is the default.
-noassert
Do not compile assertion checks. Note that the special form
assert false is always compiled because it is typed specially.
-nolabels
Ignore non-optional labels in types. Labels cannot be used in
applications, and parameter order becomes strict.
-noprompt
Do not display any prompt when waiting for input.
-nostdlib
Do not include the standard library directory in the list of
directories searched for source and compiled files.
-principal
Check information path during type-checking, to make sure that
all types are derived in a principal way. When using labelled
arguments and/or polymorphic methods, this flag is required to
ensure future versions of the compiler will be able to infer
types correctly, even if internal algorithms change. All
programs accepted in -principal mode are also accepted in the
default mode with equivalent types, but different binary
signatures, and this may slow down type checking; yet it is a
good idea to use it once before publishing source code.
-rectypes
Allow arbitrary recursive types during type-checking. By
default, only recursive types where the recursion goes through
an object type are supported.
-unsafe
Turn bound checking off on array and string accesses (the
v.(i)ands.[i] constructs). Programs compiled with -unsafe are
therefore slightly faster, but unsafe: anything can happen if
the program accesses an array or string outside of its bounds.
-version
Print version string and exit.
-w warning-list
Enable or disable warnings according to the argument warning-
list. See ocamlc(1) for the syntax of the argument.
-warn-error warning-list
Treat as errors the warnings enabled by the argument warning-
list. See ocamlc(1) for the syntax of the argument.
-help or --help
Display a short usage summary and exit.
ENVIRONMENT VARIABLES
LC_CTYPE
If set to iso_8859_1, accented characters (from the ISO Latin-1
character set) in string and character literals are printed as
is; otherwise, they are printed as decimal escape sequences.
TERM When printing error messages, the toplevel system attempts to
underline visually the location of the error. It consults the
TERM variable to determines the type of output terminal and look
up its capabilities in the terminal database.
SEE ALSO
ocamlc(1), ocamlopt(1), ocamlrun(1).
The Objective Caml users manual, chapter "The toplevel system".