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aliases

For a description of this example, please see the comments in the aliases.lgt source file.

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

%versions

Load the example:

logtalk_load(aliases(loader)).

Check the object square(_) public protocol:

%%table
square(_)::current_predicate(Predicate).

<!-- Predicate = side/1 ; Predicate = width/1 ; Predicate = height/1 ; Predicate = area/1 ; false. -->

Test the side/1 alias:

square(2)::side(Side).

<!-- Side = 2. -->

Enumerate the properties of the side/1 predicate alias:

%%table
square(2)::predicate_property(side(_), Property).

<!-- Property = alias_of(width(_56130)) ; Property = alias_declared_in(square(2)) ; Property = alias_declared_in(square(2), 52) ; Property = logtalk ; Property = scope(public) ; Property = (public) ; Property = static ; Property = declared_in(rectangle(_56350, _56352)) ; Property = declared_in(rectangle(_56350, _56352), 32) ; Property = defined_in(rectangle(_63112, _63112)) ; Property = defined_in(rectangle(_63942, _63942), 36) ; Property = number_of_clauses(1) ; Property = number_of_rules(0). -->

Enumerate the properties of the width/1 predicate:

%%table
square(2)::predicate_property(width(_), Property).

<!-- Property = logtalk ; Property = scope(public) ; Property = (public) ; Property = static ; Property = declared_in(rectangle(_3434, _3436)) ; Property = declared_in(rectangle(_3434, _3436), 32) ; Property = defined_in(rectangle(_7916, _7916)) ; Property = defined_in(rectangle(_8742, _8742), 36) ; Property = number_of_clauses(1) ; Property = number_of_rules(0). -->

Check the object circle(_) public protocol:

%%table
circle(_)::current_predicate(Predicate).

<!-- Predicate = r/1 ; Predicate = rx/1 ; Predicate = ry/1 ; Predicate = area/1 ; false. -->

Test the r/1 alias:

circle(3)::r(Radius).

<!-- Radius = 3. -->

Enumerate the properties of the r/1 predicate alias:

%%table
circle(3)::predicate_property(r(_), Property).

<!-- Property = alias_of(rx(_33998)) ; Property = alias_declared_in(circle(3)) ; Property = alias_declared_in(circle(3), 89) ; Property = logtalk ; Property = scope(public) ; Property = (public) ; Property = static ; Property = declared_in(ellipse(_34218, _34220)) ; Property = declared_in(ellipse(_34218, _34220), 69) ; Property = defined_in(ellipse(_40980, _40980)) ; Property = defined_in(ellipse(_41810, _41810), 73) ; Property = number_of_clauses(1) ; Property = number_of_rules(0). -->

Enumerate the properties of the rx/1 predicate:

%%table
circle(3)::predicate_property(rx(_), Property).

<!-- Property = logtalk ; Property = scope(public) ; Property = (public) ; Property = static ; Property = declared_in(ellipse(_46416, _46418)) ; Property = declared_in(ellipse(_46416, _46418), 69) ; Property = defined_in(ellipse(_50898, _50898)) ; Property = defined_in(ellipse(_51724, _51724), 73) ; Property = number_of_clauses(1) ; Property = number_of_rules(0). -->