diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/ur/basis.urs | 2 | ||||
| -rw-r--r-- | lib/ur/string.ur | 10 |
2 files changed, 10 insertions, 2 deletions
diff --git a/lib/ur/basis.urs b/lib/ur/basis.urs index 19983cd2..f2dffd38 100644 --- a/lib/ur/basis.urs +++ b/lib/ur/basis.urs @@ -79,7 +79,7 @@ val strsub : string -> int -> char val strsuffix : string -> int -> string val strchr : string -> char -> option string val strindex : string -> char -> option int -val strcspn : string -> string -> option int +val strcspn : string -> string -> int val substring : string -> int -> int -> string val str1 : char -> string diff --git a/lib/ur/string.ur b/lib/ur/string.ur index f19ce174..f7781e01 100644 --- a/lib/ur/string.ur +++ b/lib/ur/string.ur @@ -11,7 +11,15 @@ val suffix = Basis.strsuffix val index = Basis.strindex val atFirst = Basis.strchr -fun mindex {Haystack = s, Needle = chs} = Basis.strcspn s chs +fun mindex {Haystack = s, Needle = chs} = + let + val n = Basis.strcspn s chs + in + if n >= length s then + None + else + Some n + end fun substring s {Start = start, Len = len} = Basis.substring s start len |