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14 Cards in this Set
- Front
- Back
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\w
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letter of digit; same as [0-9A-Za-z]
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\W
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neither letter or digit
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\s
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space character; same as [ \t\n\r\f]
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\S
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non-space character
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\d
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digit character; same as [0-9]
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\D
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non-digit character
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\b (only if in a range specification)
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backspace
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\b (if not in a range specification)
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word boundary
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*
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zero or more repetitions of preceding
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+
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one or more repetitions of the preceding
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{m, n}
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at least m and at most n repetitions of the preceding
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?
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at most one repetition of the preceding; same as {0, 1}
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either preceding or next expression may match
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()
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grouping
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