From 194b0064bc21f615d3809241576e79d29ceeb7f5 Mon Sep 17 00:00:00 2001
From: Ron Kok <ronkok@comcast.net>
Date: Fri, 1 Nov 2019 09:19:06 -0700
Subject: [PATCH] Improve MathML for corners (#1922)

---
 src/macros.js  | 7 +++++++
 src/symbols.js | 8 ++++----
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/macros.js b/src/macros.js
index c4b7f7a0..f5b51c50 100644
--- a/src/macros.js
+++ b/src/macros.js
@@ -405,6 +405,13 @@ defineMacro("\u00A9", "\\copyright");
 defineMacro("\u00AE", "\\textregistered");
 defineMacro("\uFE0F", "\\textregistered");
 
+// The KaTeX fonts have corners at codepoints that don't match Unicode.
+// For MathML purposes, use the Unicode code point.
+defineMacro("\\ulcorner", "\\html@mathml{\\@ulcorner}{\\mathop{\\char\"231c}}");
+defineMacro("\\urcorner", "\\html@mathml{\\@urcorner}{\\mathop{\\char\"231d}}");
+defineMacro("\\llcorner", "\\html@mathml{\\@llcorner}{\\mathop{\\char\"231e}}");
+defineMacro("\\lrcorner", "\\html@mathml{\\@lrcorner}{\\mathop{\\char\"231f}}");
+
 //////////////////////////////////////////////////////////////////////
 // LaTeX_2ε
 
diff --git a/src/symbols.js b/src/symbols.js
index c95177bb..3acc9ed5 100644
--- a/src/symbols.js
+++ b/src/symbols.js
@@ -310,10 +310,10 @@ defineSymbol(math, ams, textord, "\u03dd", "\\digamma", true);
 defineSymbol(math, ams, textord, "\u03f0", "\\varkappa");
 
 // AMS Delimiters
-defineSymbol(math, ams, open, "\u250c", "\\ulcorner", true);
-defineSymbol(math, ams, close, "\u2510", "\\urcorner", true);
-defineSymbol(math, ams, open, "\u2514", "\\llcorner", true);
-defineSymbol(math, ams, close, "\u2518", "\\lrcorner", true);
+defineSymbol(math, ams, open, "\u250c", "\\@ulcorner", true);
+defineSymbol(math, ams, close, "\u2510", "\\@urcorner", true);
+defineSymbol(math, ams, open, "\u2514", "\\@llcorner", true);
+defineSymbol(math, ams, close, "\u2518", "\\@lrcorner", true);
 
 // AMS Binary Relations
 defineSymbol(math, ams, rel, "\u2266", "\\leqq", true);