Using Quantifiers

• * Match 0 or more times

• + Match 1 or more times

• ? Match 1 or 0 times

• {n} Match exactly n times

• {n,}  Match at least n times

• {n,m} Match at least n but not more than m times.

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Quanitifiers:

* perl -ne "print if m/z*/" testfile.txt

+ perl -ne "print if m/z+/" testfile.txt

? perl -ne "print if m/z?/" testfile.txt

{n} perl -ne "print if m/o{4}/" testfile.txt

{n,} perl -ne "print if m/o{2,}/" testfile.txt

{n,m} perl -ne "print if m/o{2,3}/" testfile.txt

n and m limited to 65,536.

Curly braces are normal in any other context (not meta).

perl -ne "print if m/{/" testfile.txt

*, +, and ? are just shorthand for what curly brace notations? {0,} {1,} {0,1}