sgn fails if the argument is a variable

[britlion]

zxb version 1.4.0-s1980

Code:

dim y as uByte=1 print sgn y print sgn 2

This wont compile. sgn <number> is fine. sgn variable isn't.

Code:

Traceback (most recent call last): File "zxb.py", line 348, in <module> File "zxb.py", line 274, in main File "ast_\ast.pyc", line 34, in visit File "arch\zx48k\translator.pyc", line 340, in visit_UNARY api.errors.InvalidOperatorError: Invalid operator "SGN" Build Failed!

Definitely a regression, as it worked fine with an older compiler!