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1. Add the PCF Regular Expression custom field.
2. Go to the Configure link for this field. You will see the page like the following example:
   
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1. 
   
2. Click

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1. the Edit Regex

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1.  link to configure the regular expression.
   
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1. 
   
2.  Click the Save button, and the regular expression will be associated to the current custom field.
   
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Using PCF - Regular Expression custom field

1. Go to an issue and edit the field with a value that does not match the regex.
   
   
    

1. If you try to save the changes, an error message appears. Otherwise, here are some usage examples for this type of custom field.
   
   
   
   
2. For more regex examples use the search from RegExLib.

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