From 425b731050f48739749cd99c29c15aa011dbcabb Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Sun, 13 Aug 2017 12:24:06 -0700
Subject: [PATCH] LaTeX reader: Allow @ as a letter in control sequences.
@ is commonly used in macros using `\makeatletter`.
Ideally we'd make the tokenizer sensitive to `\makeatletter`
and `\makeatother`, but until then this seems a good change.
---
src/Text/Pandoc/Readers/LaTeX.hs | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/src/Text/Pandoc/Readers/LaTeX.hs b/src/Text/Pandoc/Readers/LaTeX.hs
index 4852d02c7..0edfc498d 100644
--- a/src/Text/Pandoc/Readers/LaTeX.hs
+++ b/src/Text/Pandoc/Readers/LaTeX.hs
@@ -320,8 +320,12 @@ totoks (lin,col) t =
case T.uncons rest of
Nothing -> [Tok (lin, col) Symbol (T.singleton c)]
Just (d, rest')
- | isLetter d ->
- let (ws, rest'') = T.span isLetter rest
+ | isLetterOrAt d ->
+ -- \makeatletter is common in macro defs;
+ -- ideally we should make tokenization sensitive
+ -- to \makeatletter and \makeatother, but this is
+ -- probably best for now
+ let (ws, rest'') = T.span isLetterOrAt rest
(ss, rest''') = T.span isSpaceOrTab rest''
in Tok (lin, col) (CtrlSeq ws) ("\\" <> ws <> ss)
: totoks (lin,
@@ -367,6 +371,8 @@ totoks (lin,col) t =
where isSpaceOrTab ' ' = True
isSpaceOrTab '\t' = True
isSpaceOrTab _ = False
+ isLetterOrAt '@' = True
+ isLetterOrAt c = isLetter c
isLowerHex :: Char -> Bool
isLowerHex x = x >= '0' && x <= '9' || x >= 'a' && x <= 'f'