Remove leading spaces and/or one newline from code blocks

listings is space-sensitive, so the common idiom

    <<block name>>=
    block body
    @

gets typeset as

    ⟨block name⟩≡

      block body

This is ugly, so remove all leading spaces up to the first newline (and
that newline itself, if appropriate) in each code block.

1 files changed, 11 insertions, 1 deletions

diff --git a/src/Weave.hs b/src/Weave.hs
index f10617f..f2d7836 100644
--- a/src/Weave.hs
+++ b/src/Weave.hs
@@ -23,9 +23,19 @@ weaveFragment :: Fragment -> String
 weaveFragment (Documentation text) = text
 weaveFragment (BlockCode name body) =
   "\\begin{LytBlockCode}{" ++ name ++ "}\n"
-  ++ concatMap weaveCodeOrReference body
+  ++ weaveBlockBody body
   ++ "\\end{LytBlockCode}\n"
 
+weaveBlockBody :: [CodeOrReference] -> String
+weaveBlockBody ((Code first):rest) =
+  {- The first block is code.  To make sure it gets typeset correctly, drop
+  everything up to the first newline or non-space character. -}
+  (case dropWhile (==' ') first of
+     '\n' : first' -> first'
+     first' -> first')
+  ++ concatMap weaveCodeOrReference rest
+weaveBlockBody blocks = concatMap weaveCodeOrReference blocks
+
 weaveCodeOrReference :: CodeOrReference -> String
 weaveCodeOrReference (Code text) = text
 weaveCodeOrReference (Reference name) = "\\LytFragmentReference{" ++ name ++ "}"