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 Documentation / Mathematica / Built-in Functions / Programming / Pattern Matching  /
Pattern

  • s : obj represents the pattern object obj, assigned the name s.
  • The name s must be a symbol.
  • The object obj can be any pattern object.
  • When a transformation rule is used, any occurrence of s on the right-hand side is replaced by whatever expression it matched on the left-hand side.
  • The operator : has a comparatively low precedence. The expression x:_+_ is thus interpreted as x:(_+_), not (x:_)+_.
  • The form s _ is equivalent to s :_. Similarly, s _ h is equivalent to s :_ h, s __ to s :__, and so on.
  • See the Mathematica book: Section 2.3.3Section A.2.7.

    Further Examples

    The definition applies only when the argument of gamma is an integer.

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