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Diffstat (limited to 'Lua')
| -rw-r--r-- | Lua/README.md | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/Lua/README.md b/Lua/README.md index f58e952..25ccf5f 100644 --- a/Lua/README.md +++ b/Lua/README.md @@ -6,11 +6,31 @@ roughly equivalent in usefulness to LPEG, but with a smaller codebase (roughly ## API +The Lua `bp` bindings provide the following methods: + +```lua +bp.match(text, pattern, [start_index]) --> match, match_start, match_length / nil +bp.replace(text, pattern, replacement, [start_index]) --> text_with_replacements, num_replacements +``` + +Match objects returned by `bp.match()` are tables whose `__tostring` will +return the text of the match. Additionally, match objects store the text of the +match at index `0`, and any captures stored as match objects with a key +corresponding to the capture's identifier (e.g. `@"a" @foo="bc"` will be +encoded as `{[0]="abc", [1]="a", foo={[0]="bc"}}`. If multiple captures within +a match share the same identifier, it is unspecified which captured match will +be stored at that key, so it's best to be unambiguous. + +All methods will raise an error with a descriptive message if the given pattern +has a syntax error. + +## Example Usage + ```lua local bp = require("bp") local m, i, len = bp.match("like finding a needle in a haystack", '"n" @Es=+`e "dle"') ---> {[0]="needle", Es={[0]="ee"}} +--> {[0]="needle", Es={[0]="ee"}}, 16, 6 --> tostring(m) == "needle", tostring(m.Es) == "ee" -local replaced = bp.match("like finding a needle in a haystack", '"n" +`e "dle"', "cat") ---> "like finding a cat in a haystack" +local replaced, nreplacements = bp.match("like finding a needle in a haystack", '"n" +`e "dle"', "cat") +--> "like finding a cat in a haystack", 1 ``` |