From 8afdc71a76ce4248ebc63f65b4adf3dc94425dc7 Mon Sep 17 00:00:00 2001
From: Tim Bradshaw <tfb@cley.com>
Date: Tue, 3 Dec 2019 19:50:13 +0000
Subject: [PATCH] Simplified MathJax

Rather than generating script tags, this now simply wraps suitable
delimiters around the maths, which MathJax will then find.  This is
essentially because I could not work out how to make the script tags
work with MatJax 3.

In fact I can't work out how the script tags ever worked: there doesn't
seem to be any mention of embedding maths this way even for MathJax 2:
all the focus is on using delimiters which MathJax looks for.

In both MathJax 2 and 3 this makes the output look nicer: using the
script approach seems to result in maths which, unless you apply
additional styling, is blue, while this approach results in maths which
is just ordinary.

This change

- only changes the output when using MathJax;
- makes the output simpler in that case;
- makes the formatted output better-looking I think;
- works with at least MathJax 2 as well as 3.
---
 markdown/markdown.scrbl | 3 +--
 markdown/parse.rkt      | 6 ++----
 markdown/test.rkt       | 6 ++----
 3 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/markdown/markdown.scrbl b/markdown/markdown.scrbl
index 3774ae5..74c0c68 100644
--- a/markdown/markdown.scrbl
+++ b/markdown/markdown.scrbl
@@ -234,8 +234,7 @@ Markdown Extra} and
 
 @item{Support for math-jax expressions --- inline within @litchar{\\(}
 and @litchar{\\)} delimiters and display within @litchar{\\[} and
-@litchar{\\]} delimiters --- resulting in @tt{script} elements with
-@tt{type=math/tex}.}
+@litchar{\\]} delimiters --- resulting in eqivalent markup in the output.}
 
 ]}
 
diff --git a/markdown/parse.rkt b/markdown/parse.rkt
index 887433a..be93d78 100644
--- a/markdown/parse.rkt
+++ b/markdown/parse.rkt
@@ -637,14 +637,12 @@
 (define $math-jax-inline
   (try (pdo (string "\\\\(")
             (xs <- (many1Till $anyChar (try (string "\\\\)"))))
-            (return `(script ([type "math/tex"])
-                             ,(list->string xs))))))
+            (return (string-append "\\(" (list->string xs) "\\)")))))
 
 (define $math-jax-display
   (try (pdo (string "\\\\[")
             (xs <- (many1Till $anyChar (try (string "\\\\]"))))
-            (return `(script ([type "math/tex; mode=display"])
-                             ,(list->string xs))))))
+            (return (string-append "\\[" (list->string xs) "\\]")))))
 
 (define $math-jax
   (<or> $math-jax-inline
diff --git a/markdown/test.rkt b/markdown/test.rkt
index 295737f..adeb0ab 100644
--- a/markdown/test.rkt
+++ b/markdown/test.rkt
@@ -930,11 +930,9 @@
                       (!HTML-COMMENT () " more")))))
   ;; https://github.com/greghendershott/markdown/issues/52
   (check-md "\\\\(ax^2 + bx + c = 0\\\\)"
-            '((p () (script ((type "math/tex"))
-                            "ax^2 + bx + c = 0"))))
+            '((p () "\\(ax^2 + bx + c = 0\\)")))
   (check-md "\\\\[ax^2 + bx + c = 0\\\\]"
-            '((p () (script ((type "math/tex; mode=display"))
-                            "ax^2 + bx + c = 0"))))
+            '((p () "\\[ax^2 + bx + c = 0\\]")))
   ;; but single \ still escapes as usual and the contents are still
   ;; parsed as markdown:
   (check-md "\\(some *italic* text\\)"