4.9.5 Load Context

When a Prolog source file is being read in, some aspects of the load context can be accessed by the built-in predicate prolog_load_context/2, which accesses the value of a given key. The available keys are:

source

The absolute path name of the file being loaded. During loading of a PO file, the corresponding source file name is returned.

file

Outside included files (see Include Declarations) this is the same as the source key. In included files this is the absolute path name of the file being included.

directory

The absolute path name of the directory of the file being loaded. In included files this is the directory of the file being included.

module

The source module (see ref-mod-mne). This is useful for example if you are defining clauses for user:term_expansion/6 and need to access the source module at compile time.

stream

The stream being loaded. This key is not available during loading of a PO file.

term_position

A term representing the stream position of the last clause read. This key is not available during loading of a PO file.