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Comment: Missing items in example list.

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Why does this code fail?

Code Block

def matcher = "/home/me/script/test.groovy" =~ /\.groovy/
assert matcher.matches()

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So "/\.groovy/" is just a subsequence.
You must use

Code Block

def matcher =  "/home/me/script/test.groovy" =~ /.*\.groovy/

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A pattern is not very useful alone. He's just waiting input to process through a matcher.

Code Block

def pattern =  ~/groovy/
def matcher = pattern.matcher('my groovy buddy')

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A matcher with /groovy/ pattern finds a matching subsequence in the 'my groovy buddy' sequence.
On the contrary the whole sequence doesn't match the pattern.

Code Block

def m = c.matcher('my groovy buddy')
assert m.find()
assert m.matches() == false

Application: to filter a list of names.

Code Block
languagegroovy
def list = ['groovy', '/a/b/c.groovy', 'myscript.groovy', 'groovy.rc', 'potatoes', 'groovy.']
// find all items whom a subsequence matches /groovy/
println list.findAll{ it =~ /groovy/ }  // => [ "groovy", "/a/b/c.groovy", "myscript.groovy", "groovy.rc", "groovy." ]

// find all items who match exactly /groovy/
println list.findAll{ it ==~ /groovy/ } // => [ "groovy" ]

// find all items who match fully /groovy\..*/ ('groovy' with a dot and zero or more char trailing)
println list.findAll{ it ==~ /groovy\..*/ } // => ["groovy.rc", "groovy."]

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