* Nested environments of macro definitions
* Rename environment -> namespace
* \def support
* Clean up \df@tag at beginning
* \global\def support
* Fix \global via new setMacro helper
* Fix caching behavior and build array on top of it
Also avoid double lookup of macros
* Add tests
* Add argument tests
* Remove global pointer
* Note about macros object being modified
* add __defineMacro
* Add \global\def test
* More \global tests
* Constant-time lookup
Rewrite to use an "undo" stack similar to TeX, so get and set are
constant-time operations. get() still has to check two objects: one with all
current settings, and then the built-ins. Local set() sets the current value
and (when appropriate) adds an undo operation to the undo stack. Global set()
still takes time linear in the number of groups, possibly changing the undo
operation at every level.
`Namespace` now refers to a space of things like macros or lengths.
* Add \def to-dos
* Put optional arguments in their own group
* Rename `pushNamespace` -> `beginGroup`
* Wrap each expression in a group namespace
* Add comments
* Tag sketch
* Drop objectAssign; already using Object.assign elsewhere
* Basic \gdef support
* Bug fix
* Finish \tag
* MathML numbers equations with <mlabeledtr>
* Fix flow bugs
* \gdef tests
* Add basic \tag tests
* Screenshot test for \tag
* \tag* test
* Add missing file
* Bug fix screenshot
* Major refactor
* Represent tag at top level of parse tree, requiring less hackery
* No more \@tag function; it was essentially just doing \text
* Wrap tag in group so e.g. ( and ) are formatted the same
* Add `feed` method to MacroExpander for multiple inputs (for tag)
* Bug fixes in buildHTML, makeTextRow, _getBuilt (for display mode)
* Remove excess <mrow> wrapper when unnecessary
* Update screenshot from tag being wrapped in group
* Add maxExpand limit
* Move test helpers into common modules
* helpers.js gets all the helper functions
* setup.js gets the common Jest setup (serializer, expect extensions)
* Exclude test from coverage testing
* @ylemkimon's comments: parsing -> building, settings || defaultSettings
* Default argument for settings
* Fix lint errors
* @ylemklemon's comment: use buildAndSetResult
* Use template literals
