Perl Best Practices [Electronic resources] نسخه متنی

B.11. Chapter 12, Regular Expressions

• Always use the /x flag. [Extended Formatting ]

• Always use the /m flag. [Line Boundaries ]

• Use \A and \z as string boundary anchors. [String Boundaries ]

• Use \z, not \Z, to indicate "end of string". [End of String ]

• Always use the /s flag. [Matching Anything ]

• Consider mandating the Regexp::Autoflags module. [Lazy Flags ]

• Use m{...} in preference to /.../ in multiline regexes. [Brace Delimiters ]

• Don't use any delimiters other than /.../ or m{...}. [Other Delimiters ]

• Prefer singular character classes to escaped metacharacters. [Metacharacters ]

• Prefer named characters to escaped metacharacters. [Named Characters ]

• Prefer properties to enumerated character classes. [Properties ]

• Consider matching arbitrary whitespace, rather than specific whitespace characters. [Whitespace ]

• Be specific when matching "as much as possible". [Unconstrained Repetitions ]

• Use capturing parentheses only when you intend to capture. [Capturing Parentheses ]

• Use the numeric capture variables only when you're sure that the preceding match succeeded. [Captured Values ]

• Always give captured substrings proper names. [Capture Variables ]

• Tokenize input using the /gc flag. [Piecewise Matching ]

• Build regular expressions from tables. [Tabular Regexes ]

• Build complex regular expressions from simpler pieces. [Constructing Regexes ]

• Consider using Regexp::Common instead of writing your own regexes. [Canned Regexes ]

• Always use character classes instead of single-character alternations. [Alternations ]

• Factor out common affixes from alternations. [Factoring Alternations ]

• Prevent useless backtracking. [Backtracking ]

• Prefer fixed-string eq comparisons to fixed-pattern regex matches. [String Comparisons ]