Fletch makes a good point about Switch, but if you need to fake it and make it look like a switch (although the lookup example is succinct and readable), you could do this, which I've done in the past:

for ($var) {
/cat/ && do { ...; last };
/dog/ && do { ...; last };
warn "$var Nothing matched\n";
}
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Pretty basic, and it has a similar feel. Just use the for to assign the value to $_ and then use pattern matching for your "case"s. Kind of similar to the shell's case ... in syntax. However, coding it as a lookup, or using some other idiom is usually a better bet.