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* '''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.'' |
* '''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.'' |
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* '''Regular expression''': ''This is the regular expression pattern used to perform matches and captures on the '''String to test'''.<br />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 '''#/'''.'' |
* '''Regular expression''': ''This is the regular expression pattern used to perform matches and captures on the '''String to test'''.<br />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 '''#/'''.'' |
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* '''Mode''': ''(Optional, defaults to 0 |
* '''Mode''': ''Sets the mode in which Regex() will run. Optional, defaults to 0.'' |
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** 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.'' |
** '''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.'' |
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** 1 - 9: ''Outputs the specified N<sup>th</sup> 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''' - '''9''': ''Outputs the specified N<sup>th</sup> 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.'' |
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** -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.'' |
** '''-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.'' |
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* '''Case sensitivity''': ''Toggles the case-sensitivity of regular expressions. |
* '''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.'' |
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** 0: ''Ignore case when matching (e.g. the letters '''E''' and '''e''' are identical). This is the default.'' |
** 0: ''Ignore case when matching (e.g. the letters '''E''' and '''e''' are identical). This is the default.'' |
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** 1: ''Consider case when matching (e.g. the letters '''E''' and '''e''' are considered different).'' |
** 1: ''Consider case when matching (e.g. the letters '''E''' and '''e''' are considered different).'' |
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<br>'''<nowiki>listbuild(1, \, if(Regex([Artist],/#([[:punct:]])#/, 0), Contains Punctuation\[R1], No Punctuation), [Artist])&DataType=[list]</nowiki>'''<br>''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.'' |
<br>'''<nowiki>listbuild(1, \, if(Regex([Artist],/#([[:punct:]])#/, 0), Contains Punctuation\[R1], No Punctuation), [Artist])&DataType=[list]</nowiki>'''<br>''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.'' |
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A more complex example that removes semicolon and backslash characters, which cause problems when building a list... |
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<pre> |
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if(Regex([Artist], /#([[:punct:]])#/, 0), |
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Contains Punctuation\replace(replace([R1], ;,Semicolon), \, Backslash), |
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No Punctuation)\replace(replace([Artist], ;, / and/ ), \, //)&DataType=[list] |
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</pre> |
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... IN PROGRESS... |
... IN PROGRESS... |
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Revision as of 05:58, 28 August 2011
Note: The File Properties page is now at its permanent home ==> File_Properties_(tags)
Note: This is MrC's working space for Wiki page work-in-progress.
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.) |
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Construction | Regex(String to test, Regular expression, Mode, Case sensitivity)
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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:
Sample output:
Sample output:
Sample output:
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... |