x %if_next_is% y
x %if_next_isnt% y
x %if_prev_is% y
x %if_prev_isnt% y
Arguments
x
A regex pattern.
y
A regex pattern.
Details
These functions provide an interface to perl lookarounds.
Special binary functions are used to infer an ordering, since often you
might wish to match a word / set of characters conditional on the start
and end of that word.