cmark

diff --git a/Makefile b/Makefile
@@ -178,7 +178,7 @@ dingus: js/commonmark.js
 ### Spec ###
 
 spec.md: $(SPEC)
-	python3 spec2md.py $< > $@
+	python3 makespec.py $< markdown > $@
 
 spec: spec.html
 	@anchors=`perl -ne '@matches = / id="([^"]*)"/g; foreach $$match (@matches) { print "$$match\n"; }' $<`; \
@@ -188,11 +188,8 @@ spec: spec.html
 			 echo "Link to missing anchor #$$link"; \
 	done
 
-spec.html: spec.md template.html
-	pandoc --no-highlight --number-sections --template template.html -s --toc -S $< | \
-	perl -pe 's/a href="@([^"]*)"/a id="\1" href="#\1" class="definition"/g' | \
-	perl -pe 's/␣/<span class="space"> <\/span>/g' \
-	> $@
+spec.html: spec.txt template.html
+	python3 makespec.py $< html > $@
 
 spec.pdf: spec.md template.tex specfilter.hs
 	pandoc -s $< --template template.tex \

diff --git a/makespec.py b/makespec.py
@@ -0,0 +1,77 @@
+#!/usr/bin/env python3
+import re
+import sys
+from subprocess import *
+
+if len(sys.argv) == 3:
+    specfile = sys.argv[1]
+    specformat = sys.argv[2]
+    if not (specformat in ["html", "markdown"]):
+        sys.stderr.write("Format must be html or markdown\n")
+        exit(1)
+else:
+    sys.stderr.write("Usage:  makespec.py SPECFILE [html|markdown]\n")
+    exit(1)
+
+def pipe_through_prog(prog, text):
+    p1 = Popen(prog.split(), stdout=PIPE, stdin=PIPE, stderr=PIPE)
+    [result, err] = p1.communicate(input=text.encode('utf-8'))
+    return [p1.returncode, result.decode('utf-8'), err]
+
+def replaceAnchor(match):
+    refs.append("[{0}]: #{1}".format(match.group(1), match.group(2)))
+    return '<a id="{1}" href="#{1}" class="definition">{0}</a>'.format(match.group(1), match.group(2))
+
+stage = 0
+example = 0
+section = ""
+mdlines = []
+refs = []
+
+with open(specfile, 'r', encoding='utf-8') as spec:
+    for ln in spec:
+        if re.match(r'^\.$', ln):
+            if stage == 0:
+                example += 1
+                mdlines.append("\n<div class=\"example\" id=\"example-{0}\" data-section=\"{1}\">\n".format(example, section))
+                mdlines.append("<div class=\"examplenum\"><a href=\"#example-{0}\">Example {0}</a>&nbsp;&nbsp;<a class=\"dingus\" title=\"open in interactive dingus\">(interact)</a></div>\n\n".format(example))
+                mdlines.append("````````````````````````````````````````````````````````` markdown\n")
+                stage = 1
+            elif stage == 1:
+                mdlines.append("`````````````````````````````````````````````````````````\n\n")
+                mdlines.append("````````````````````````````````````````````````````````` html\n")
+                stage = 2
+            elif stage == 2:
+                mdlines.append("`````````````````````````````````````````````````````````\n\n")
+                mdlines.append("</div>\n")
+                stage = 0
+            else:
+                sys.stderr.out("Encountered unknown stage {0}\n".format(stage))
+                sys.exit(1)
+        else:
+            if stage == 0:
+                match = re.match(r'^#{1,6} *(.*)', ln)
+                if match:
+                    section = match.group(1)
+                else:
+                    ln = re.sub(r'\[([^]]*)\]\(@([^)]*)\)', replaceAnchor, ln)
+            else:
+                ln = re.sub(r' ', '␣', ln)
+            mdlines.append(ln)
+
+mdtext = ''.join(mdlines) + '\n\n' + '\n'.join(refs) + '\n'
+
+if specformat == "markdown":
+    sys.stdout.write(mdtext)
+elif specformat == "html":
+    prog = "pandoc -s --toc -S --no-highlight --number-sections --template template.html"
+    [retcode, result, err] = pipe_through_prog(prog, mdtext)
+    if retcode == 0:
+        result = re.sub(r'␣', '<span class="space"> </span>', result)
+        sys.stdout.write(result)
+    else:
+        sys.stderr.write("Error converting markdown version of spec:\n")
+        sys.stderr.write(err)
+        exit(1)
+
+exit(0)

diff --git a/spec2md.py b/spec2md.py
@@ -1,50 +0,0 @@
-#!/usr/bin/env python3
-import re
-import sys
-
-stage = 0
-example = 0
-section = ""
-mdlines = []
-refs = []
-
-if len(sys.argv) > 1:
-    specfile = sys.argv[1]
-else:
-    specfile = 'spec.txt'
-
-with open(specfile, 'r', encoding='utf-8') as spec:
-    for ln in spec:
-        if re.match(r'^\.$', ln):
-            if stage == 0:
-                example += 1
-                mdlines.append("\n<div class=\"example\" id=\"example-{0}\" data-section=\"{1}\">\n".format(example, section))
-                mdlines.append("<div class=\"examplenum\"><a href=\"#example-{0}\">Example {0}</a>&nbsp;&nbsp;<a class=\"dingus\" title=\"open in interactive dingus\">(interact)</a></div>\n\n".format(example))
-                mdlines.append("````````````````````````````````````````````````````````` markdown\n")
-                stage = 1
-            elif stage == 1:
-                mdlines.append("`````````````````````````````````````````````````````````\n\n")
-                mdlines.append("````````````````````````````````````````````````````````` html\n")
-                stage = 2
-            elif stage == 2:
-                mdlines.append("`````````````````````````````````````````````````````````\n\n")
-                mdlines.append("</div>\n")
-                stage = 0
-            else:
-                sys.stderr.out("Encountered unknown stage {0}\n".format(stage))
-                sys.exit(1)
-        else:
-            if stage == 0:
-                match = re.match(r'^#{1,6} *(.*)', ln)
-                if match:
-                    section = match.group(1)
-                else:
-                    for match in re.finditer(r'\[([^]]*)\]\(@([^)]*)\)', ln):
-                        refs.append("[{0}]: #{1}".format(match.group(1), match.group(2)))
-            else:
-                ln = re.sub(r' ', '␣', ln)
-            mdlines.append(ln)
-
-mdtext = ''.join(mdlines) + '\n\n' + '\n'.join(refs) + '\n'
-
-sys.stdout.write(mdtext)