Scala String trimming by a set of characters -


given set of (trailing) characters, instance 

val s = "un".toset

how trim string s, namely,

"untidy stringnu".trimby(s) res: string = tidy string

scala has dropwhile solves half of problem. has dropright that's analog drop right end of collection. unfortunately doesn't have dropwhileright, though, have creative.

if don't particularly care efficiency, can drop characters off left end, reverse, repeat, , reverse again:

scala> "untidy stringnu".dropwhile(s).reverse.dropwhile(s).reverse res0: string = tidy string

if you're sure that's going bottleneck in program (hint: it's not), you'll want kind of imperative solution.


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