* Initial implementation of block string literals following lexical_conventions/string_literals.md.
Enabled yyinput() in flex to implement parsing.
Added ParseBlockStringLiteral() helper to handler further transformations such as indenting.
Modified formar_grammar to support single-quoted strings to prevent a failure on lexer.lpp.
* Fixed _find_string_end quote parameter type int -> str.
* Update executable_semantics/syntax/BUILD
Co-authored-by: Geoff Romer <gromer@google.com>
* Addressed code review comments - split table-drived test into individual tests, renamed constants to match style guide.
* Addressed code review comments -- using EXPECT_THAT_EXPECTED() in tests, lexer comments and code cleanup.
Co-authored-by: Geoff Romer <gromer@google.com>
This is based on discussion on #732: that we should probably parse the invalid whitespace, then reject it as part of string validation, rather than having different parses. I worry the question of "how is this parsed" may lead to subtly unexpected results if we aren't consistent, so I'm switching the logic from the lexer to the unescape library (and also adjusting the list of rejected whitespace).
It was in my mind to add String in order to support libraries in `package`. `print` is added in order to have a String go to stdout. I've tried to do `print` in a way that won't be too hard to add other printable types, but it's probably also somewhat optional here -- that is, if desired, I could remove it. But it was a lot easier to doublecheck `\n` behavior with it, and I suspect it'll be helpful in other tests if it supports more value types.
On the side, this also fixes dereferencing in Pattern/Expression Print() calls, which I was noticing printing pointers instead of values. This may be another argument for moving away from passing pointers, since this seems to be a difficult-to-catch error.
Co-authored-by: Geoff Romer <gromer@google.com>
pk19604014andGeoff Romer
Jon Meow