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Regular
Expressions
101
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Unit Tests (9)
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Explanation
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Quick Reference
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All Tokens
Common Tokens
General Tokens
Anchors
Meta Sequences
Quantifiers
Group Constructs
Character Classes
Flags/Modifiers
Substitution
A single character of: a, b or c
[abc]
A character except: a, b or c
[^abc]
A character in the range: a-z
[a-z]
A character not in the range: a-z
[^a-z]
A character in the range: a-z or A-Z
[a-zA-Z]
Any single character
.
Alternate - match either a or b
a|b
Any whitespace character
\s
Any non-whitespace character
\S
Any digit
\d
Any non-digit
\D
Any word character
\w
Any non-word character
\W
Match everything enclosed
(?:...)
Capture everything enclosed
(...)
Zero or one of a
a?
Zero or more of a
a*
One or more of a
a+
Exactly 3 of a
a{3}
3 or more of a
a{3,}
Between 3 and 6 of a
a{3,6}
Start of string
^
End of string
$
A word boundary
\b
Non-word boundary
\B
Regular Expression
v6
/
/
gm
Unit Tests
given the string
UU
assert that capture group 2 equals
U
given the string
UF
assert that capture group 2 equals
F
given the string
FU
assert that capture group 2 equals
F
given the string
UT
assert that capture group 2 equals
U
given the string
TU
assert that capture group 2 equals
U
given the string
FF
assert that capture group 2 equals
F
given the string
FT
assert that capture group 2 equals
F
given the string
TF
assert that capture group 2 equals
F
given the string
TT
assert that capture group 2 equals
T
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