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3.11. Relational Operators

Perl has two classes of relational operators. One class operates on numeric values, the other on string values, as shown in Table 3-5.

Table 3.5. Relational Operators

Numeric String Meaning
> gt Greater than
>= ge Greater than or equal to
< lt Less than
<= le Less than or equal to

These operators return 1 for true and "" for false. Note that relational operators are nonassociating, which means that $a < $b < $c is a syntax error.

In the absence of locale declarations, string comparisons are based on the ASCII/Unicode collating sequences, and, unlike in some computer languages, trailing spaces count in the comparison. With a locale declaration, the collation order specified by the locale is used. (Locale-based collation mechanisms may or may not interact well with the Unicode collation mechanisms currently in development.)

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