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Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

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.. rst-class:: align-right

built-in predicate

.. index:: pair: logtalk_load/2; Built-in predicate .. _predicates_logtalk_load_2:

logtalk_load/2

Description

::

logtalk_load(File, Flags) logtalk_load(Files, Flags)

Compiles to disk and then loads to memory a :term:`source file` or a list of source files using a list of compiler flags. The Logtalk source file name extension (by default, .lgt) can be omitted. Source file paths can be absolute, relative to the current directory, or use :term:`library notation`. Compiler flags are represented as flag(value). This predicate can also be used to compile Prolog source files as Logtalk source code. When no recognized Logtalk or Prolog extension is specified, the compiler tries first to append a Logtalk source file extension and then a Prolog source file extension. If that fails, the compiler tries to use the file name as-is. For a description of the available compiler flags, please see the :ref:programming_flags section in the User Manual. The recognized Logtalk and Prolog file extensions are defined in the :term:`backend adapter files <adapter file>`. The recognized Logtalk and Prolog file extensions are defined in the :term:`backend adapter files <adapter file>`.

When this predicate is called from the top-level interpreter, relative source file paths are resolved using the current working directory. When the calls are made from a source file, relative source file paths are resolved by default using the source file directory (unless a :ref:`relative_to <flag_relative_to>` flag is passed).

Note that only the errors related to problems in the predicate argument are listed below. This predicate fails on the first error found during compilation of a source file. In this case, no contents of the source file are loaded.

.. warning::

The compiler flags specified in the second argument only apply to the files listed in the first argument and not to any files that those files may load or compile. Notably, if you are loading a :term:`loader file`, the flags only apply to the loader file itself and not to the files loaded by it.

Modes and number of proofs

::

logtalk_load(@source_file_name, @list(compiler_flag)) - zero_or_one logtalk_load(@list(source_file_name), @list(compiler_flag)) - zero_or_one

Errors

| File is a variable: | instantiation_error | Files is a variable or a list with an element which is a variable: | instantiation_error | File, or an element File of the Files list, is neither a variable nor a source file name: | type_error(source_file_name, File) | File, or an element File of the Files list, uses library notation but the library does not exist: | existence_error(library, Library) | File or an element File of the Files list, does not exist: | existence_error(file, File) | Flags is a variable or a list with an element which is a variable: | instantiation_error | Flags is neither a variable nor a proper list: | type_error(list, Flags) | An element Flag of the Flags list is not a valid compiler flag: | type_error(compiler_flag, Flag) | An element Flag of the Flags list defines a value for a read-only compiler flag: | permission_error(modify, flag, Flag) | An element Flag of the Flags list defines an invalid value for a flag: | domain_error(flag_value, Flag+Value)

Examples

::

% compile and load the "list" source file in the % current directory using default compiler flags: | ?- logtalk_load(list, []).

% compile and load the "tree" source file in the "types" % library directory with the source_data flag turned on: | ?- logtalk_load(types(tree)).

% compile and load the "file_system" source file in the % current directory with portability warnings suppressed: | ?- logtalk_load(file_system, [portability(silent)]).

.. seealso::

:ref:predicates_logtalk_compile_1, :ref:predicates_logtalk_compile_2, :ref:predicates_logtalk_load_1, :ref:predicates_logtalk_make_0, :ref:predicates_logtalk_make_1, :ref:predicates_logtalk_library_path_2