TESTING double (generic, default) formatting. Target: double
pass:
SUCCESS: 0: 0
SUCCESS: 0.5: 0.5
SUCCESS: .5: 0.5
SUCCESS: -.5: -0.5
SUCCESS: +.5: 0.5
SUCCESS: +12.345: 12.345
fail:
FAILURE: a: double
FAILURE: .-5: double
FAILURE: zaza: double
FAILURE: 3.1415a: double
