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diff --git a/scanner/README.md b/scanner/README.md new file mode 100644 index 0000000..c131a9f --- /dev/null +++ b/scanner/README.md @@ -0,0 +1,43 @@ +# Scanner + +A scanner takes a string in input and returns an array of tokens. + +Tokens can be of the following kinds: +- identifier +- number +- operator +- separator +- string +- block + +Resolving nested blocks in the scanner is making the parser simple +and generic, without having to resort to parse tables. + +The lexical rules are provided by a language specification at language +level which includes the following: + +- a set of composable properties (1 per bit, on an integer) for each + character in the ASCII range (where all separator, operators and + reserved keywords must be defined). +- for each block or string, the specification of starting and ending + delimiter. + +## Development status + +A successful test must be provided to check the status. + +- [x] numbers starting with a digit +- [ ] numbers starting otherwise +- [x] unescaped strings (including multiline) +- [x] escaped string (including multiline) +- [x] separators (in UTF-8 range) +- [x] single line string (\n not allowed) +- [x] identifiers (in UTF-8 range) +- [x] operators, concatenated or not +- [x] single character block/string delimiters +- [x] arbitrarly nested blocks and strings +- [x] multiple characters block/string delimiters +- [x] blocks delimited by operator characters +- [ ] blocks delimited by identifiers +- [x] blocks with delimiter inclusion/exclusion rules +- [ ] blocks delimited by indentation level (python, yaml, ...) |