Groovy Goodness: Multiple Assignments

Since Groovy 1.6 we can define and assign values to several variables at once. This is especially useful when a method returns multiple values and we want to assign them to separate variables.

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// Assign and declare variables. def (username, email) = ['mrhaki', 'email@host.com'] assert 'mrhaki' == username assert 'email@host.com' == email   // We can assign later than the definition of the variables. int housenr String streetname (streetname, housenr) = ['Old Street', 42] assert 42 == housenr assert 'Old Street' == streetname   // We can also use type declarations. def (String streetName, int houseNumber) = ['Old Street', 42] assert 42 == houseNumber assert 'Old Street' == streetName   // Return value of method can be assigned to multiple variables. def iAmHere() {     [29.20090, 12.90391] } def (coordX, coordY) = iAmHere() assert coordX == 29.20090 assert coordY == 12.90391   // More values than variables: extra values are ignored. def (a, b, c) = ['a', 'b', 'c', 'd'] assert 'a' == a assert 'b' == b assert 'c' == c   // Less values than variables: variable is not set. def (x, y, z) = [100, 200] assert 100 == x assert 200 == y assert !z   // Useful for getting regular expressions matching groups. def money  = '12 Euro' def regexp = /(\d+) (\w+)/ def (exp, amount, currency) = (money =~ regexp)[0] assert '12' == amount assert 'Euro' == currency