1 |
Sequence is c1c2c3.. -- a sequence of single characters
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2 |
* or {0,} is "zero or more" of previous character
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3 |
+ or {1,} is "one or more" of previous character
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4 |
? or {0,1} is "zero or one" of previous character
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5 |
All matching is greedy -- they maximize number of characters "eaten up" starting with leftmost matching
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In Perl5 one can follow specification with ? to instruct Perl5 to find smallest match (first occurrence) so that
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.*?: matches to first : in line while .*: matches to last : in line.
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6 |
Curly Brace Notation:
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7 |
c{n1,n2} means from n1 to n2 instances of character c
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8 |
c{n1,} means n1 or more instances of character c
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9 |
c{n1} means exactly n1 instances of character c
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10 |
c{0,n2} means n2 or less instances of character c
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