S.I/Lisp/

CONSTANCY

=CONSTANCY(123, 456)
-> 123

=CONSTANCY("y = mx + b", "a^2 + b^2 = c^2")
-> "y = mx + b"

=CONSTANCY(#CALC!, #NULL!)
-> #CALC!

=CONSTANCY(IDENTITY, CONSTANCY)
-> IDENTITY
        

DEFINE(
    CONSTANCY,
    LAMBDA(
        x,
        y,
        x))
        

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