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Regex(...): Regular expression pattern matching

Regex() This function performs regular expression (RE) pattern matching on its input. It can be used in one of three different modes: a test mode to test for a match, a capture output mode to output the specified captured pattern, and a silent, capture-only mode. All match captures are placed into special variables referenced as [R1], [R2], ... [R9], which can be used in subsequent expressions. The contents of the captures [R1] ... [R9] are available until the entire expression completes, or Regex() is run again, whereby they are replaced. (Available since build 16.0.155.)
Construction Regex(String to test, Regular expression, Mode, Case sensitivity)
  • String to test: One or more library fields, plain text, or a combination of both, which is used as the string evaluated for a match.
  • Regular expression: This is the regular expression pattern used to perform matches and captures on the String to test.
    The regular expression language assigns special meaning to many characters. A few of these meta-characters, such as forward slash "/", comma "," and parenthesis "(" and ")", are also used by the Media Center expression language. To force the Media Center expression engine to ignore the meta-characters in regular expressions, surround the entire regular expression with /# and #/. This is Media Center's form of escapement, which tells the expression engine to ignore everything inside, so that the entire, uninterpreted regular expression can be provided to the Regex() regular expression evaluator. Although /# and #/ is not necessary when no conflicting characters are in use, and you may manually escape such characters with a forward slash "/", it is best practice to always encase a regular expression in /# and #/.
  • Mode: Sets the mode in which Regex() will run. Optional, defaults to 0.
    • 0: Runs in test mode, returning 1 or 0, indicating whether the string matched (1) or did not match (0) the pattern. This mode is useful within an if() test, so that different true (1) or false (0) actions may be taken. There is no output in this mode. This mode is the default.
    • 1 - 9: Outputs the specified Nth capture group's contents, where N ranges from 1 to 9. Currently, only a single capture is output in this mode, but all captures are available in the [R1] ... [R9] capture variables. This mode is used to easily output a single matching sub-string.
    • -1: Runs in silent mode, with no output. This mode is useful as a means to capture portions of the string, and later use those captures in subsequent portions of an expression.
  • Case sensitivity: Toggles the case-sensitivity of regular expressions. Optional, defaults to 0, ignoring case. To use this option, a value or comma-placeholder must also be set for the Mode option.
    • 0: Ignore case when matching (e.g. the letters E and e are identical). This is the default.
    • 1: Consider case when matching (e.g. the letters E and e are considered different).
Examples Regex([Name], /#(Big.*Man)#/, 1)
Matches track names that contain Big followed by Man, with anything (including nothing) in between, and outputs the matched tracks.

Sample output:

Big Butter and Egg Man
Big Man
Big Manager
It's a Bigman Thing


Regex([Artist], /#([(].+)$#/, 1)
Matches against the Artist field and returns items that contain an opening (left) parenthesis followed by additional characters until the end of the artist string. Only the sub-string from any opening parenthesis until the end of the string will be returned, since this is the only captured portion.

Sample output:

(Brian Eno/U2)
(feat. DJ Cam)
(Otis Day & The Knights)
(w/Emmylou Harris)


Regex([Name], /#([(][^)]+)$#/, 1)
Similar to the previous example, but matches track names that contain a opening (left) parenthesis, but are missing the closing (right) parentheses through the end of the track name. This might be useful to help detect tagging inconsistencies

Sample output:

(feat. David Bowie


if(Regex([Artist],/#([[:punct:]])#/, 0),[R1] --> [Artist],No Punctuation)
Matches against the Artist field looking for any punctuation character. The results of the Regex() expression will be a 0 (false) or 1 (true) since the mode is set to 0, The true side of the if() test is set to output the first (and only) capture, which is expressed as [R1], and is followed by the string " --> " and then the artist name. In the false case, the string "No Punctuation" is output.

Sample output:

"  --> Clarence "Frogman" Henry
& --> Al Cohn & Zoot Sims
.  --> Dr. John
/  --> Bootsy Collins/Fatboy Slim


listbuild(1, \, if(Regex([Artist],/#([[:punct:]])#/, 0), Contains Punctuation\[R1], No Punctuation), [Artist])&DataType=[list]
Similar to the previous example, but when used inside an expression column, builds an expandable tree with headings Contains Punctuation or No Punctuation, thus reducing the excessive number of entries that would be produced.

→ Contains Punctuation
→ $
Payola$
→ +
→ :
→ No Punctuation


listbuild(1, \, if(Regex([Artist],/#([[:punct:]])#/, 0), Contains Punctuation\[R1], No Punctuation), [Artist])&DataType=[list]
Similar to the previous example, but when used inside an expression column, builds an expandable tree with headings Contains Punctuation or No Punctuation, thus reducing the excessive number of entries that would be produced.

A more complex example that removes semicolon and backslash characters, which cause problems when building a list...

if(Regex([Artist], /#([[:punct:]])#/, 0),
     Contains Punctuation\replace(replace([R1], ;,Semicolon), \, Backslash),
     No Punctuation)\replace(replace([Artist], ;, / and/ ), \, //)&DataType=[list]

... IN PROGRESS...