identifier #

	insert(<mi>#</mi>)

number #

	insert(<mi>#</mi>)

\sqrt

	replace($, <msqrt>$</msqrt>)

\root

	replace($, <mroot><mrow/><mrow>$</mrow></mroot>)

\of

	when (isa($.parent, "mrow") && isa($.parent.parent, "mroot"))
	let mroot = $.parent.parent
	if ($.prev and !$.prev.prev and !$.next) replace($.parent, $.prev)
	replace(mroot.child[0], $)

\underline

	insert(<munder>[$, <mo>&UnderBar;</mo>]</munder>)

\overline

	insert(<mover>[$, <mo>&OverBar;</mo>]</mover>)

\cases

	replace($, <mrow><mo>{</mo><mtable>$</mtable></mrow>)

\matrix

	replace($, <mtable>$</mtable>)

\over

	if isa($.parent, "mrow")
		replace($.parent, <mfrac>[$.parent, $]</mfrac>)


_	if isa($.parent, "mrow")
		if eq($.prev, null)
			replace($, new(mmultiscripts, [ new mrow, $, new none ]))
		elseif (isa($.prev, msub))
			let base = $.prev.children[0]
			let script = $.prev.children[1]
			replace($.rev, new(mmultiscripts, [ base, script, new none, $, new none ]))
		elseif (isa($.prev, msup))
			let base = $.prev.children[0]
			let script = $.prev.children[1]
			replace($.prev, new(msubsup, [ base, $, script ]))
		elseif (isa($.prev, msubsup))
			let base = $.prev.children[0]
			let subscript = $.prev.children[1]
			let superscript = $.prev.children[2]
			replace($.prev, new(mmultiscripts, [ base, subscript, superscript, $, new none ]))
		elseif isa($.prev, mmultiscripts)
			if ($.prev.children[$.prev.children.size - 2] = null)
				replace($.prev.children[$.prev.children.size - 2], $)
			else
				$.prev.children.append([$, new none])
		else
			replace($.prev, new(msub, [ $.prev, $ ]))
	else if isa($.parent, msub) and $.parent.children[1] = $
		let base = $.parent.children[0]
		replace($.parent, new(munder, [ base, $ ]))

		
_, \sb (subscript)

	if parent.isa(mrow)
		if cursor is first child then
			sub = new mmultiscripts
			parent.replace(cursor, sub);
			sub.set_base(new mrow);
			sub.set_subscript(cursor);
		else
			elem = element prior to cursor in parent
			if elem.isa(msub) || elem.isa(msup) || elem.isa(mmultiscripts) then
				append script to multiscript and/or replace single script with
				multiscript
			else if elem.isa(munder) || elem.isa(mover) || elem.isa(munderover) then
				creates another munder
			else
				parent.replace(elem, sub);
				sub.set_base(elem);
				sub.set_subscript(cursor);
	else if (parent.isa(msub) and cursor is subscript) or
		change msub into a munder
		cursor in same position
	else
		replace cursor with msub with empty base

^, \sp (superscript)

	symmetric to subscript

', \prime (prime)

	similar to superscript, but multiple prime superscripts should go
	together in the same operator

{	(group open)

	replace cursor with mrow, put cursor inside mrow
	if cursor is inside a table, create a new table row and a new table cell
	and put the cursor inside the cell

}	(group close)

	remove cursor from mrow
	mrow.parent.advance(cursor, mrow)
	if cursor inside a table cell then close table
	
\over,\atop,\above (fraction)

	if cursor.parent.isa(mrow) then
		frac = new mfrac
		cursor.parent.parent.replace(mrow, frac)
		numerator is current content of cursor.parent except for the cursor
		itself.
		set denominator to cursor
	else

\choose

	similar to fractions, but with stretchable parentheses around

\sqrt

	parent.replace(cursor, new msqrt)
	set new msqrt.base to cursor

\root

	parent.replace(cursor, new mroot)
	set empty base element
	set root index to cursor

\of

	check if cursor.parent is mroot (or mrow inside mroot index)
	or and cursor is in index position. move the cursor to the base element

\underline

	create munder element with stretchable horizontal line as underscript
	substitute cursor with munder
	move the cursor in the base element

\overline

	symmetric

accents (\hat)

	create an mover with accent=true and the operator has stretchy=false

wide accents (\widehat)

	as accents, but mover has accent=false and the operator has stretchy=true

\scriptstyle, ...

	create an appropriate mstyle, the cursor moves in. However, when the
	subformula ends one has to skip the mstyle

\cases

	create mrow with stretchable brace and emtpy table, put cursor inside
	table

\matrix

	create empty table, cursor inside table

&

	check that cursor is inside a table cell
	create a new cell next to it

\cr

	check that cursor is inside a table cell inside a table row
	create a new row

\phantom

	create a mphantom element, cursor inside