(awk-edits) Added initial MEL parser

2 files changed, 104 insertions, 0 deletions

diff --git a/awk-edits/#stack.awk b/awk-edits/#stack.awk
new file mode 100644
index 0000000..a8b0b2a
--- /dev/null
+++ b/awk-edits/#stack.awk
@@ -0,0 +1,26 @@
+function newStack(name) {
+	__stacks[name, "length"] = 0
+}
+
+function topStack(name) {
+	return __stacks[name, __stacks[name, "length"] - 1]
+}
+
+function lengthStack(name) {
+	return __stacks[name, "length"]
+}
+
+function pushStack(name, value) {
+	__stacks[name, __stacks[name, "length"]++] = value
+}
+
+function popStack(name, value) {
+	delete __stacks[name, --__stacks[name, "length"]]
+}
+
+function deleteStack(name) {
+	for (i = 0; i < __stacks[name, "length"]; i++) {
+		delete __stacks[name, i]
+	}
+	delete __stacks[name, "length"]
+}
diff --git a/awk-edits/MEL-parser.awk b/awk-edits/MEL-parser.awk
new file mode 100644
index 0000000..ebd68bd
--- /dev/null
+++ b/awk-edits/MEL-parser.awk
@@ -0,0 +1,78 @@
+# .*(slides|teaching)/.*html
+#
+# == About ==
+#
+# MEL is the "Markdown Extensions Language"
+# It's a general metalanguage (I made) for adding custom syntax to Markdown (via awk)
+# The idea is it provides parsing for general constructs, and you only need to define
+# the names of those constructs and with what they get replaced with
+#
+# Slightly based on ftags, this system allows you to easily implement the following construts:
+# &(name ... &)    Multiline "tag", everything inside is formatted by "name"
+# &{name ... &}    In practice, it just replaces "&[name" and "&]" with the appropriate HTML
+# &[name ... &]    All three can be used interchangeably, though it's preferrable if
+#                  you use the matching braces and semantically, in your "language"
+#                  square brackets are used for the largest components
+#                  curly for structural components and normal braces for styling
+# &:name           Format/encapsulate everything until the end of the paragraph
+# &::name          Format/encapsulate everything until the end of the line
+# &.name           Insert standalone element as-is
+#
+# Though it's not decided (or implemented) yet, potentially there will also be:
+# &)-(    Used to simplify cases of &(name1 ... &) &(name1 ... &) &(name1 ... &)
+# &}-{                         into &(name1 ... &)-( ... &)-( ... &)
+# &]-[    Or maybe for special cases, where rather than doing something like
+#         &{elementsList &(element1 ... &) &(element2 ... &) &}
+#         you could simply do
+#         &{elementsList ... &}-{ ... &}-{ ... &}
+#         So it will surf as a separator between direct subelements
+
+BEGIN {
+	newStack("mel")
+	MELSINGLE = "s"
+	MELOPEN   = "o"
+	MELCLOSE  = "c"
+}
+
+/<code>/ {
+	melInsideCode = 1
+}
+
+/<\/code>/ {
+	melInsideCode = 0
+}
+
+melInsideCode == 0 && /^[ \t]*(<p>)?&#38;/ {
+	newLine = ""
+	lineCopy = $0
+	while (match(lineCopy, /&#38;(((::|[[{(:.])[^[:space:].:[{(<>)}\]&]+)|[\]})])/)) {
+		RSTART  = RSTART + 5
+		RLENGTH = RLENGTH - 5
+
+		# Inside closing tag
+		if (RLENGTH == 1) {
+			replaceWith = MEL[topStack("mel"), MELCLOSE]
+			popStack("mel")
+		}
+		# Inside opening tag
+		else if (substr(lineCopy, RSTART, 1) ~ /[[{(]/) {
+			name = substr(lineCopy, RSTART + 1, RLENGTH - 1)
+
+			replaceWith = MEL[name, MELOPEN]
+			pushStack("mel", name)
+		}
+		# Inside paragraph/one line/insert
+		# TODO: currently all work as insert
+		else {
+			nameStart = 1 + (substr(lineCopy, RSTART + 1, 1) == ":")
+			name = substr(lineCopy, RSTART + nameStart, RLENGTH - nameStart)
+
+			replaceWith = MEL[name, MELSINGLE]
+		}
+		newLine = newLine substr(lineCopy, 0, RSTART - 6) replaceWith
+		lineCopy = substr(lineCopy, RSTART + RLENGTH)
+	}
+	$0 = newLine lineCopy
+	if (length(newLine) > 0)
+		gsub(/(<p>|<\/p>)/, "")
+}