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This tool detects likely dead code in Logtalk entities and in Prolog modules
compiled as objects. Predicates (and non-terminals) are classified as dead code
when (1) there is no scope directive for them and (2) are not called, directly
or indirectly, by any predicate with a (local or inherited) scope directive.
Predicates (and non-terminals) listed in
but that are not used are also classified as dead code.
Besides dead code, this tool can also help detect other problems in the code
that often result in reporting false positives. For example, typos in
directives, missing scope directives, and missing
Given the possibility of false positives, care must be taken before deleting reported dead code to ensure that it's, in fact, code that is not used. A common cause of false positives is the use of conditional compilation directives to provide implementations for predicates missing in some systems.
dead_code_scanner.lgt source file implements the scanning predicates for
finding dead code in entities, libraries, and directories. The source file
dead_code_scanner_messages.lgt defines the default translations for the
messages printed when scanning for dead code. These messages can be intercepted
to customize output, e.g. to make it less verbose, or for integration with e.g.
GUI IDEs and continuous integration servers.
To consult this tool API documentation, open in a web browser the link:
For sample queries, please see the SCRIPT.txt file.
This tool can be loaded using the query:
| ?- logtalk_load(dead_code_scanner(loader)).
Use of local meta-calls with goal arguments only known at runtime can result
in false positives. When using library or user-defined meta-predicates, it
can be helpful to compile the source files with the
optimize flag turned
on so that the meta-calls may be resolved at compile time and thus allow
calling information for the meta-arguments to be recorded, avoiding false
positives for predicates that are only meta-called.
All source files are formatted using tabs (the recommended setting is a tab width equivalent to 4 spaces).