This commit introduces environments, and implements the parser
infrastructure to handle them, even including arguments after the
“\begin{name}” construct. It also offers a way to turn array-like data
structures, i.e. delimited by “&” and “\\”, into nested arrays of groups.
Environments are essentially functions which call back to the parser to
parse their body. It is their responsibility to stop at the next “\end”,
while the parser takes care of verifing that the names match between
“\begin” and “\end”. The environment has to return a ParseResult, to
provide the position that goes with the resulting node.
One application of this is the “array” environment. So far, it supports
column alignment, but no column separators, and no multi-column shorthands
using “*{…}”. Building on the same infrastructure, there are “matrix”,
“pmatrix”, “bmatrix”, “vmatrix” and “Vmatrix” environments. Internally
these are just “\left..\right” wrapped around an array with no margins at
its ends. Spacing for arrays and matrices was derived from the LaTeX
sources, and comments indicate the appropriate references.
Now we have hard-wired breaks in parseExpression, to always break on “}”,
“\end”, “\right”, “&”, “\\” and “\cr”. This means that these symbols are
never PART of an expression, at least not without some nesting. They may
follow AFTER an expression, and the caller of parseExpression should be
expecting them. The implicit groups for sizing or styling don't care what
ended the expression, which is all right for them. We still have support
for breakOnToken, but now it is only used for “]” since that MAY be used to
terminate an optional argument, but otherwise it's an ordinary symbol.
Summary:
On https://app.asana.com/0/34646644303310/33935538887378, @eater requested we add some new colors to KaTeX, which lives in the spin-off Khan/KaTeX open source project. (See screenshot for colors.) I added these colors to KaTeX so math typesetting tools in exercises have access to them.
I used "blueA", "blueB", etc. because dashes and numbers aren't supported in KaTeX/LaTeX functions.
The actual mapping of color name => hex value is in "Options", and the listing of colors available for typesetting is in "functions".
See also https://phabricator.khanacademy.org/D18158 for the related additions to utils/math.js and KAthJax.
Test Plan:
- Set up the KaTeX dev environment (instructions taken from https://github.com/Khan/KaTeX/blob/master/CONTRIBUTING.md):
```
cd KaTeX
make setup
make serve
```
- Now that the server is up and running, visit http://localhost:7936/ to try live typesetting. Enter the following LaTeX code to try the new colors:
```
\blueE{e=mc^2}
```
- Try other new colors including \redD, \mintC, \grayH, \kaBlue, etc.
- Old colors like \orange should still work.
- Run the Jasmine test suite at http://localhost:7936/test/test.html.
Reviewers: emily
Reviewed By: emily
Subscribers: nataliefitzgerald, eater, cameron, david
Differential Revision: https://phabricator.khanacademy.org/D18152
Summary:
Use the TeX definitions of `\root` to get the optional `\sqrt`
argument in the right place. Also add the MathML version.
Fixes#48
Test Plan:
- `make test`
- See that the images look good
Reviewers: kevinb, alpert
Reviewed By: alpert
Differential Revision: https://phabricator.khanacademy.org/D17236
Summary:
The greediness of the `\color` function wasn't set correctly,
leading to expressions like `\color{red}\text{a}` parsing correctly,
when they shouldn't. (This is based on how MathJax parses, since TeX
doesn't have a `\color` function, so MathJax is the standard).
Test Plan:
- Make test
- See that `\color{red}\text{a}` doesn't parse (like MathJax)
- See that `\color{red}{\text{a}}` does parse (like MathJax)
- See that `\color{red}\frac12` doesn't parse (like MathJax)
- See that `\color{red}{\frac12}` does parse (like MathJax)
- See that `\red\text{a}` doesn't parse (like MathJax)
- See that `\red{\text{a}}` does parse (like MathJax)
- See that `\red\frac12` doesn't parse (like MathJax)
- See that `\red{\frac12}` does parse (like MathJax)
Reviewers: alpert
Reviewed By: alpert
Differential Revision: https://phabricator.khanacademy.org/D17130
Summary:
Using \phantom with non-phantom math in Perseus doesn't render to be the
same size because \phantom uses MathJax and the non-phantom math uses KaTeX.
Implementing \phantom in KaTeX should solve this alignment issue.
Test Plan:
[x] write (and run) unit tests
[x] create (and run) screenshotter tests
Reviewers: emily
Reviewed By: emily
Differential Revision: https://phabricator.khanacademy.org/D16720
Summary:
This adds support for rendering KaTeX to both HTML and MathML
with the intent of improving accessibility. To accomplish this, both
MathML and HTML are rendered, but with the MathML visually hidden and
the HTML spans aria-hidden. Hopefully, this should produce much better
accessibility for KaTeX.
Should fix/improve #38Closes#189
Test Plan:
- Ensure all the tests, and the new tests, still pass.
- Ensure that for each of the group types in `buildHTML.js`, there is a
corresponding one in `buildMathML.js`.
- Ensure that the huxley screenshots didn't change (except for
BinomTest, which changed because I fixed a bug in `buildHTML` where
`genfrac` didn't have a `groupToType` mapping).
- Run ChromeVox on the test page, render some math. (for example,
`\sqrt{x^2}`)
- Ensure that a mathy-sounding expression is read. (I hear "group
square root of x squared math").
- Ensure that nothing else is read (like no "x" or "2").
- Ensure that MathML markup is generated correctly and is interpreted
by the browser correctly by running
`document.getElementById("math").innerHTML =
katex.renderToString("\\sqrt{x^2}");` and seeing that the same speech
is read.
Reviewers: john, alpert
Reviewed By: john, alpert
Subscribers: alpert, john
Differential Revision: https://phabricator.khanacademy.org/D16373
Summary:
Add the ability to pass in options to the render calls which contain information about the parse. This information is passed around to the parser and builder, which parse and render differently depending on the options. Currently, this includes an option to render the math in display mode (i.e. centered, block level, and in displaystyle).
Also added some changes to make it easier to add new data to functions (now that new data doesn't need to be copied into the ParseFuncOrArg data structure, it is looked up when it is needed) and has more sane support for the `'original'` argType (as suggested by pull request #93).
Test Plan:
- Make sure tests and lint pass
- Make sure huxley screenshots didn't change, and new screenshot looks correct
Reviewers: alpert
Reviewed By: alpert
Differential Revision: https://phabricator.khanacademy.org/D13810
Summary:
Add correct parsing of optional arguments. Now, things like `\rule` can shift
based on its argument, and parsing of `\sqrt[3]{x}` fails (correctly) because we
don't support that yet.
Also, cleaned up the lexing code a bit. There was a vestige of the old types in
the lexer (they have now been completely moved to symbols.js). As a byproduct,
this made it hard to call `expect("]")`, because it would look at the type of
the Token and the type for "]" was "close". Now, all functions just look at the
text of the parsed token, and in special occasions (like in the dimension lexer)
it can return some data along with it.
Test Plan:
- Make sure tests still work, and new tests work
- Make sure no huxley screenshots changed
- Make EXTRA SURE `\sqrt[3]{x}` fails.
Reviewers: alpert
Reviewed By: alpert
Differential Revision: http://phabricator.khanacademy.org/D13505
changed stopType (string) parameter to breakOnInfix (boolean)
renamed rewriteInfixNodes to handleInfixNodes
added a test for {1 \over 2} \over 3, fixed some grammar, and added code in the parser to squash superfluous ordgroups
removed squashOrdGroups and instead don't create an "ordgroup" if one already exists
removed unnecessary variable
moved variable declarations out of "if" statements
removed comment
Fixed style issue with where variables are declared and remove unnecessary comment from functions.js