groovy - Is if(!x) the same as if(x!=null) -


i know sort of duplicate of is if(pointervar) same if(pointervar!=null)?, have ask anyway.

in groovy, have following:

def x = somemethod() if( !x ) {    // stuff }

this standard null check, ie (x != null), right?

no. if in groovy calls underlying asboolean() method. known groovy truth.

empty lists, empty strings, empty maps, null, 0, falsy values:

if ([:]) {     assert false }  if (null) {     assert false }  if ("") {     assert false }  if (0) {     assert false }  assert null.asboolean() == false  assert 1.asboolean()

you can write asboolean in own classes.


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