In Pharo 7.0, ```arcTan:``` has been redesigned to use ```signBit``` instead of ```sign``` (in order to detect IEEE-754 negative-zero). ```PMComplex``` miss this method.
In Pharo 7.0,
arcTan:has been redesigned to usesignBitinstead ofsign(in order to detect IEEE-754 negative-zero).PMComplexmiss this method.