diff options
Diffstat (limited to 'src/interp/lexing.boot')
| -rw-r--r-- | src/interp/lexing.boot | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/src/interp/lexing.boot b/src/interp/lexing.boot index 4b357918..36b54fd5 100644 --- a/src/interp/lexing.boot +++ b/src/interp/lexing.boot @@ -44,6 +44,22 @@ module lexing where matchString: %String -> %Maybe %Short matchAdvanceString: %String -> %Maybe %Short matchAdvanceKeyword: %Symbol -> %Thing + indentationLocation: %String -> %Maybe %Short + +--% + +++ Return the logical indentation position in the `line', after +++ expansion of leading vertical tab characters. +indentationLocation line == + loc := 0 + n := #line + for i in 0.. repeat + i >= n => return nil + spaceChar? line.i => loc := loc + 1 + tabChar? line.i => loc := 8 * (loc quo 8 + 1) + return loc + +--% --% --% Line abstract datatype |