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# ?Term1 @< ?Term2

Succeeds if term Term1 is before term Term2 in the standard ordering.

Term1
  An arbitrary term.
Term2
  An arbitrary term.

## Description

Succeeds if term Term1 precedes term Term2 in the standard ordering of terms.

See compare/3 for the definition of this standard ordering.

### Modes and Determinism

- @<(?, ?) is semidet

### Fail Conditions

Fails if Term1 does not precede Term2.

## Examples

       Success:
       X @< 1.0.           (gives X = _g68)
       0.0 @< 1.
       2.0 @< 1.
       "a" @< a.
       atoma @< atomb.
       [a|b] @< [a,b].
       b(1) @< a(1,1).
       a(1,2,3,4.0) @< a(1,2,3,0).
       Fail:
       1.0 @< X.
       atomb @< atoma.
       f(1,1) @< f(1).

## See Also

compare / 3, @> / 2, @=< / 2, @>= / 2