> On 17 Feb 2019, at 23:10, Peng Yu <pengyu...@gmail.com> wrote: > > This lexical tie-in creates feedback from the parser to the lexer. So > the lexer cannot be tested standalone. > > But the principle of separating lexer and parser is to make parser > builtin on top of the parser. Is there something that can avoid the > feedback yet still allow context-dependent parsing? Alternatively, how > to just testing the lexer without having to get the parser involved?
The LARL(1) that Bison uses is for context free grammars only, so contexts must involve switches somehow. Think of a definition which changes a name into an identifier, implemented by putting it on a (typically stacked) lookup table, which the lexer checks, and returns its token value to the parser. A grammar definition alone would require an attribute grammar. _______________________________________________ help-bison@gnu.org https://lists.gnu.org/mailman/listinfo/help-bison
