Logtalk reference manual
Built-in method: expand_goal/2

expand_goal/2

Description

expand_goal(Goal, Expansion)

Expands a goal.

The expansion works as follows: if the first argument is a variable, then it is unified with the second argument; if the first argument is not a variable and clauses for the goal_expansion/2 predicate are within scope, then this predicate is called to provide an expansion that is then unified with the second argument; if the call to the goal_expansion/2 predicate fails, the two arguments are unified.

Goal expansion is only performed by the Logtalk compiler to expand the body of clauses read from a source file.

Template and modes

expand_goal(?term, ?term)

Errors

(none)

Examples

(none)