number/1

tests whether the argument is a number.

number(+Term)

number/1 succeeds if Term is a number otherwise it fails.

Arguments 

Term                   term

Examples

number(-11.3). Succeeds.
number(100). Succeeds.
number(Number). Fails.
X is 3, Y is 2, number(X+Y). Fails.

Standard

This predicate is part of the ISO-Prolog Standard.

See also

atom/1, atomic/1, compound/1, float/1, integer/1, nonvar/1, var/1.

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