gbdev/rgbds
1
0
Fork 0
mirror of https://github.com/gbdev/rgbds.git synced 2025-11-20 10:12:06 +00:00
Code Issues Packages Projects Releases Wiki Activity

Avoid treating labels and macros differently in column 1 (#1515)

Browse Source 
Fixes #1512
This commit is contained in:
Sylvie
2024-09-22 19:26:25 -04:00
committed by GitHub
parent 15919e550f
commit 6b89938da7
9 changed files with 75 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/asm/lexer.cpp
View File

@@ -1849,7 +1849,19 @@ static Token yylex_NORMAL() {
}
}
if (token.type == T_(ID) && (lexerState->atLineStart || peek() == ':'))
// This is a "lexer hack"! We need it to distinguish between label definitions
// (which start with `LABEL`) and macro invocations (which start with `ID`).
//
// If we had one `IDENTIFIER` token, the parser would need to perform "lookahead"
// to determine which rule applies. But since macros need to enter "raw" mode to
// parse their arguments, which may not even be valid tokens in "normal" mode, we
// cannot use lookahead to check for the presence of a `COLON`.
//
// Instead, we have separate `ID` and `LABEL` tokens, lexing as a `LABEL` if a ':'
// character *immediately* follows the identifier. Thus, at the beginning of a line,
// "Label:" and "mac:" are treated as label definitions, but "Label :" and "mac :"
// are treated as macro invocations.
if (token.type == T_(ID) && peek() == ':')
token.type = T_(LABEL);
return token;