Extension To Postfix Style

variable += value
variable -= value

is used for adding or removing the specific value.

x  = a b c d
x -= b

becoms

x = a c d

.

Another case,

x  = a b c d
x += e

becomes

x = a b c d e

.

Copyright (C) 1993-2022 Ken'ichi Fukamachi mail:< fukachan at fml.org >