Provide a pattern to a crossword puzzle, (e.g. T _ A _) and find words matching that pattern.

xwordFinder.groovy

@groovy.transform.Field String pattern = 'A__S__E'

class XWordCategory {
    static boolean matchesPattern(String self, String pattern) {
          pattern == null ? false : self ==~ pattern.replace('_', /\w{1}/)
    }
}

use(XWordCategory) {
    assert 'KEPI'.matchesPattern('____')
    assert 'KEPI'.matchesPattern('K___')
    assert 'KEPI'.matchesPattern('_E__')
    assert 'KEPI'.matchesPattern('__P_')
    assert 'KEPI'.matchesPattern('___I')
    assert 'KEPI'.matchesPattern('KE__')
    assert 'KEPI'.matchesPattern('K_P_')
    assert 'KEPI'.matchesPattern('K__I')
    assert 'KEPI'.matchesPattern('KEP_')    
    assert 'KEPI'.matchesPattern('KE_I')
    assert 'KEPI'.matchesPattern('_EPI')
    assert 'KEPI'.matchesPattern('KEPI')
    assert 'KEPI'.matchesPattern('_____') == false    
    assert 'KEPI'.matchesPattern('___') == false
    assert 'KEPI'.matchesPattern('T___') == false
    assert 'KEPI'.matchesPattern('_A__') == false

    /* d/l http://svn.pietdepsi.com/repos/projects/zyzzyva/trunk/data/words/North-American/OWL.txt as local file */    
    new File(/C:\Users\jwolf2\Desktop\dictionary.txt/).eachLine { line ->
        def word = line.split(' ')[0]
        if (word.matchesPattern(pattern)) {
            println line
        }
    }
    
}