Equality Operators
The equality operators listed in Table 3.6 are much like the relational operators.
Table 3-6. Equality Operators
| Numeric | String | Meaning |
|---|---|---|
== | eq | Equal to |
!= | ne | Not equal to |
<=> | cmp | Comparison, with signed result |
The equal and not-equal operators return 1
for true and "" for false (just as the relational operators do). The
<=> and cmp operators
return -1 if the left operand is less than the
right operand, 0 if they are equal, and
+1 if the left operand is greater than the right.
Although the equality operators appear to be similar to the relational
operators, they do have a lower precedence level, so $a <
$b <=> $c < $d is syntactically valid.
For reasons that are apparent to anyone who has seen
Star Wars, the <=>
operator is known as the "spaceship" operator.
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