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Predicate upcase_atom/2
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LogicalCaptain said (2021-05-22T22:11:18):0 upvotes 0 0 downvotes
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?- upcase_atom('aAbB12',X).
X = 'AABB12'.
?- upcase_atom("aAbB12",X).
X = 'AABB12'.

For strings, there is the differently named string_upper/2

?- string_upper('aAbB12',X).
X = "AABB12".

?- string_upper("aAbB12",X).
X = "AABB12".