mathlive/CHANGELOG.md

Render and edit beautifully typeset math

## 0.59.0 (2020-11-04)

### Breaking Change

    - Renamed `getCaretPosition()` and `setCaretPosition()` to `get/set caretPoint`
    and `setCaretPoint()`. "Position" refers to an index denoting the boundaries
    between elements making up the formula.

### New Feature

    - **#555** Support for IME (Input Method Engines) for Japanese, Chinese,
    Korean and other complex scripts.
    - `find()` method to search the fragments of an expression that matches
    a string or regular expression.

### Improvements

    - Improved handling of paste commands: if a JSON item is on the clipboard
    it is used in priority, before a `plain/text` item.
    - It is now possible to type dead keys such as `alt+e`, and they are
    properly displayed as a composition.

## 0.58.0 (2020-10-11)

### New Features

-   **#225** Added `onCommit` listener to `mf.options`. This listener is invoked when
    the user presses **Enter** or **Return** key, or when the field loses focus
    and its value has changed since it acquired it.
    In addition, a `change` event is triggered when using a `MathfieldElement`.
    The event previously named `change` has been renamed to `input`.
    This mimics the behavior of `<input>` and `<textarea>` elements.
-   **#225** Changed the keyboard shortcuts to add columns and rows:
    | Shortcut | Command |
    |:---|:---|
    | **ctrl**/**cmd** + **Return**/**Enter** | `addRowAfter` |
    | **ctrl**/**cmd** + **shift** + **Return**/**Enter** | `addRowBefore` |
    | **ctrl**/**cmd** + **;** | `addRowAfter` |
    | **ctrl**/**cmd** + **shift** + **;** | `addRowBefore` |
    | **ctrl**/**cmd** + **,** | `addColumnAfter` |
    | **ctrl**/**cmd** + **shift** + **,** | `addColumnBefore` |

    Note that **Enter**/**Return** no longer create a matrix/vector when inside a parenthesized expression. Use **ctrl/cmd** + **Return**/**Enter** instead.

-   Added a `commit` command to programmatically trigger the `onCommit` listener
    `change` event.
-   Added `mount` and `unmount` events to `MathfieldElement`
-   The `$text()` method, which is deprecated, was accidentally prematurely removed.
    It has been added back.

### Bug Fixes

-   Inline shortcuts would not always be triggered correctly,
    for example `x=sin` -> `x\sin` instead of `x=\sin`
-   The text in tooltip was not vertically centered in narrow layouts (mobile devices)
-   **#668** Extensible symbols, such as `\xrightarrow` were incorrectly
    treated as if they had an invisible boundary, resulting in the cursor
    being positioned incorrectly when navigating with the keyboard.

## 0.57.0 (2020-10-09)

### Major New Feature

This release introduce two major new features which will require code changes.
For now, the older API remains supported but it will be dropped in an
upcoming release.

#### **#665: Web Component**

Support for `MathfieldElement` custom element/web component and `<math-field>` tag.

The `makeMathField()` method is still supported, but it will be removed in an upcoming version. You should transition to using `<math-field>` or
`MathfieldElement` instead.

This transition require the following changes:

1.  Create mathfields using `MathfieldElement` or declaratively

```javascript
// Before
let mf = MathLive.makeMathField(document.createElement('div'), {
    virtualKeyboardMode: 'manual',
});
mf.$latex('f(x) = \\sin x');
document.body.appendChild(mf.$el());

// After
let mfe = new MathfieldElement({
    virtualKeyboardMode: 'manual',
});
mfe.value = 'f(x) = \\sin x';
document.body.appendChild(mfe);
```

or:

```html
<math-field virtual-keyboard-mode="manual">f(x) = \sin x</math-field>
```

2.  Use events instead of callbacks

```javascript
    // Before
    mf.setConfig({ onContentDidChange: (mf) => {
        console.log(mf.$latex())
    });

    // After
    mfe.addEventListener('input', (ev) => {
        console.log(mfe.value);
    });
```

#### **#667 Modernized Public API**

Support for web component is an opportunity to revisit the MathLive public API and modernize it.

The goals are:

-   clarity. For example, the `$latex()` can be used to read or change the content of the mathfield.
-   expressiveness. For example, `$selectedText()` can return the value of the selection,
    but there is no way to inspect (or save/restore) the selection.
-   consistency with web platform APIs when applicable, otherwise following the [**monaco**](https://github.com/Microsoft/monaco-editor/blob/master/monaco.d.ts) (VSCode editor) or [**CodeMirror**](https://codemirror.net/doc/manual.html#api) conventions primarily. As part of this proposal, the APIs of **TinyMCE**, **CKEditor** and **QuillJS** were also considered. For example, the method equivalent to `getConfig()` is called `getOptions()` in most
    Javascript text editor libraries.

**Mathfield methods**

The following `Mathfield` methods have been renamed as indicated:

| Before                       | After                                    |
| :--------------------------- | :--------------------------------------- |
| `$setConfig()`               | `setOptions()`                           |
| `getConfig()`                | `getOptions()` and `getOption()`         |
| `$text()`                    | `getValue()`                             |
| `$latex()`                   | `value`, `getValue()` and `setValue()`   |
| `$insert()`                  | `insert()`                               |
| `$hasFocus()`                | `hasFocus()`                             |
| `$focus()`                   | `focus()`                                |
| `$blur()`                    | `blur()`                                 |
| `$selectedText()`            | `mf.getValue(mf.selection)`              |
| `$selectionIsCollapsed()`    | `mf.selection[0].collapsed`              |
| `$selectionDepth()`          | `mf.selection[0].depth`                  |
| `$selectionAtStart()`        | `mf.position === 0`                      |
| `$selectionAtEnd()`          | `mf.position === mf.lastPosition`        |
| `$select()`                  | `select()`                               |
| `$clearSelection()`          | `executeCommand('delete-previous-char')` |
| `$keystroke()`               | `executeCommand()`                       |
| `$typedText()`               | `executeCommand('typed-text')`           |
| `$perform()`                 | `executeCommand()`                       |
| `$revertToOriginalContent()` | n/a                                      |
| `$el()`                      | n/a                                      |
| n/a                          | `selection`                              |
| n/a                          | `position`                               |

The methods indicated with "n/a" in the **After** column have been dropped.

Only the new methods are available on `MathfieldElement` (i.e. when using web components). The `Mathfield` class retains both the old methods and the
new ones to facilitate the transition, but the old ones will be dropped
in an upcoming version.

There is also a new `selection` property on `Mathfield` and `MathfieldElement`
which can be used to inspect and change the selection and a `position`
property to inspect and change the insertion point (caret).

The `getValue()` method also now take an (optional) `Range`, which is
the type of the `selection` property, to extract a fragment of the expression.

**Default Exports**

While default exports have the benefits of expediency, particularly when converting an existing code base to ES Modules, they are problematic for effective tree shaking. Therefore the default export will be eliminated.

This means that instead of:

```javascript
import Mathlive from 'mathlive';
Mathlive.renderMathInDocument();
```

you will need to use:

```javascript
import { renderMathInDocument } from 'mathlive';
renderMathInDocument();
```

The following functions have been renamed:

| Before                            | After                           |
| :-------------------------------- | :------------------------------ |
| `MathLive.latexToAST()`           | Use MathJSON                    |
| `MathLive.latexToMarkup()`        | `convertLatexToMarkup()`        |
| `MathLive.latexToMathML()`        | `convertLatexToMathMl()`        |
| `MathLive.latexToSpeakableText()` | `convertLatexToSpeakableText(`) |

### New Features

-   **#101**: added `getCaretPosition()` and `setCaretPosition()`

### Improvements

-   The Typescript types for `Selector` has been improved
-   The Typescript type for `getOptions()` (`getConfig()`) are more accurate
-   The "sqrt" inline shortcut now inserts an argument
-   Don't throw an error if the first argument of `\enclose` is empty
-   **#591**: add `upward` and `downward` hooks when navigating out of the
    mathfield (now also sent as a `focus-out` event)
-   Improved layout of the virtual keyboard on narrow mobile devices (fill the available width).

### Bug Fixes

-   **#198**: typing backspace while typing inline shortcuts would prevent the
    shortcuts from being recognized
-   **#573**: brackets were not properly styled (i.e. color applied to them)
-   **#543**: spurious focus/blur events were dispatched if `tabIndex` was
    set to 0 on the mathfield and some area of the mathfield were clicked on.
    The issue was that with `tabIndex="0"` the mathfield frame would be focusable
    and when that happened the focus would correctly switch to the invisible
    `<textarea>` element which is normally focused to receive keyboard events,
    but this generated an incorrect `blur` event (for the container losing focus)
    and an incorrect `focus` event (for the `<textarea>` gaining focus)
-   **#599**: some characters, for example "ü", would not be correctly parsed or
    displayed. Note that technically, those characters are ignored by TeX,
    but it's a reasonable behavior nowadays to accept them as input.
-   **#628**: typing "e" repeatedly inside a matrix would corrupt the emited
-   **#637**: in Chrome, thin lines, such as fraction bars or square root lines
    would not display at some zoom levels
-   The locale was not properly taking into account when it was set manually
-   The `config.strings` property did not reflect the state of the localization strings
-   When configs was updated (e.g. new macros added), the content of the mathfield was not properly re-parsed and rendered
-   When making the virtual keyboard visible, the mathfield would not be focused
-   The virtual keyboard would not display correctly when the mathfield was inside a shadow DOM

### Special Thanks

-   Thanks to `@stefnotch` for contributing several of the improvements in this
    release

## 0.56.0 (2020-08-22)

### New Features

-   Added support for `\phantom`, `\vphantom`, `\hphantom` and `\smash[]`
-   **#182** Added support for the mhchem package, with the commands `\ce` and `\pu` to
    display chemical equations

## 0.55.0 (2020-08-17)

### New Features

-   **WebPack issues workaround and font loading configuation**

    Follow up to **#508**. The fonts can now be loaded either statically or dynamically.

    -   **dynamic loading** by default, the fonts will get loaded programmatically
        when they are needed and the rendering will be deferred until the fonts
        are available to avoid unnecessary redrawing. Use this technique if you
        have a simple build/bundle workflow. You can still customize the relative
        path to the fonts folder using the `fontsDirectory` configuration option.

    -   **static loading** include the `mathlive-fonts.css` stylesheet in your
        page. The loading of this file will trigget the font to be loaded
        asynchronously by the browser. Use this technique if you are using
        WebPack or have a build/bundle workflow that renames the font files or
        in general require the bundler to know about the required assets.

-   **New packaging options**. The distribution files have been split between
    minified and non-minified version. In the more common cases, the minified
    version (`mathlive.min.js` and `mathlive.min.mjs` should be used). The
    non-minified version (`mathlive.js` and
    `mathlive.mjs` can be used to help in debugging issues or to apply patches).

### Bug Fixes

-   The fonts failed to load when loading MathLive using a `<script>` tag and
    a CDN. The fonts folder is now resolved correctly with the following configurations:

        - `<script>` tag and CDN
        - `<script>` tag and local file
        - `import` and CDN
        - `import` and local file

## 0.54.0 (2020-06-24)

### Bug Fixes

-   **#490** Firefox does not load fonts
    There is a bug in Firefox (https://bugzilla.mozilla.org/show_bug.cgi?id=1252821)
    where the status of fonts is reported incorrectly.

    Implemented a workaround by always loading fonts in Firefox.

-   **#506** Chrome was outputing a harmless warning about passive event listeners.
    The warning has been silenced.

-   **#505** Chrome was outputing a harmless warning about passive event listeners.
    The warning has been silenced with extreme prejudice.

-   **#503** Dynamic styles were not applied inside of shadow DOM

## 0.53.3 (2020-06-24)

### Bug Fixes

-   **#504** "Spacing is inconsistent after editing"

    The spacing of operators should be adjusted depending on what's around them:
    there is less space after a "-" sign when used as an infix operator than there
    is around a "-" sign used as a prefix operator (i.e. "-4" vs "3-4").

    The code that was handling this was accounting for it by modifying the type of
    the element. This worked well enough for static rendering, but for dynamic
    rendering (i.e. editing), once modified the previous type of the element was
    lost and could not be restored (i.e. after deleting the atom in front of a "-"
    sign, the "-" was no longer a binary operator but a regular symbol).

    This is now handled during layout without modifying the type of the element.

-   Workaround for a Safari bug where in some cases the caret would not blink.

-   **#505** More consistent spacing between elements. Previously some Unicode
    math spacing characters were used. However, these characters are not
    rendered consistently. Switched to using CSS margins instead.

-   The Latex generated for a `\left` command with another command as a
    fence was lacking a space, e.g. `\left\lbracka\right\rbrack` instead of
    `\left\lbrack a\right\rbrack`

-   Smart fence for square brackets was not working correctly.

-   Fixed smartmode to avoid converting a decimal point to text when entering,
    e.g. "314.1576"

-   The alt/option+V shortcut now correctly inserts a placeholder in the square root

-   The "\arcos" function was incorrectly spelled "\arccos".

### New Feature

-   **#508** In order to better support some deployment configurations, added
    a 'mathlive-fonts.css' file to the distribution package.

    This is intended to be used by build/bundle environements that have an
    asset pipeline that can move/rename assets, including the font-files

    Note that this method is **not** recommended. It will result in some cases
    where the layout is incorrect until the page is reloaded (especially for
    formulas using large symbols such as integrals or large parentheses).

    To use it, add the following to the web pages using MathLive:

```html
<link rel="stylesheet" href="dist/mathlive-fonts.css" />
```

## 0.53.2 (2020-06-10)

### Bug Fixes

-   Adjusted height of square root (there was some extra blank space above)
-   Ensure that the 'dt' inline shortcut does not trigger when writing "width"
    (it should only apply in the math mode)
-   **#492** Typing "/" to insert as fraction when some items were selected
    would result in an eroneous output.

## 0.53.1 (2020-06-01)

### Bug Fixes

-   In the virtual keyboard, use `\scriptstyle` to display small symbols
-   Better vertical alignment of extensible arrows
-   Don't display a double caret after a `\leftright`

## 0.53.0 (2020-05-31)

### Breaking Change / New Feature

-   **#158** The CSS files `mathlive.css` and `mathlive.core.css` have been deprecated and removed from the distribution.

    The necessary CSS is now injected dynamically into the page. This simplifies the use of the library, but also reduces the amount of CSS in the page, potentially improving performance. That's particularly the case when the virtual keyboard is not used, as the CSS stylesheet for the virtual keyboard is substantial, and it is now injected only when the keyboard is used.

    To transition, you should remove from your code any instance of:

    ```html
    <link rel="stylesheet" href="mathlive.core.css" type="text/css" />
    <link rel="stylesheet" href="mathlive.css" type="text/css" />
    ```

    (the path to your CSS file may be different).

    You may need to specify the location of the 'fonts' directory. By default,
    the 'fonts' directory is expected to be next to the 'mathlive.js',
    'mathlive.mjs' file. If you need to copy the 'fonts' directory to a different
    location, specify it using the `Config.fontsDirectory` option. It should be
    either a relative path or a full URL pointing to the directory that contains
    the fonts. (Fix for **#425**)

    You no longer need to manually specify the stylesheets when using
    `renderMathInElement()` or `renderMathInDocument()` either.
    The necessary stylesheet will get injected in the
    document as needed. Note that this stylesheet for these functions is
    smaller than the stylesheet used when
    the editor is in use. These two functions also gain a property to specify the
    location of the 'fonts' directory, if necessary (by default, the 'fonts'
    directory is expected to be next to the 'mathlive.js', 'mathlive.mjs' file.)

    In some rare cases, you may have used the CSS stylesheet without the Mathlive library, for example, after you may have saved the output of `latexToMarkup()` to a database
    and use it to render later in a page. In that case, you would need to use the
    CSS styelsheet `dist/mathlive-static.css`, which is suitable for this use case.
    Note that it does reference a 'fonts' folder that may need to be adjusted. By
    default, the `fonts` folder should be placed next to the stylesheet. If you
    need a different location when using the static stylesheet, you will need
    to modify it.

-   **#425** Added CSS variable `--ML_keyboard-zindex` to control the zindex
    of the virtual keyboard.

-   Add support for `^^` and `^^^^` constructs in Latex. See TexBook p. 56:

        There’s also a special convention in which ^^ is followed by two
        “lowercase hexadecimal digits,” 0–9 or a–f. With this convention, all 256 characters are
        obtainable in a uniform way, from ^^00 to ^^ff. Character 127 is ^^7f.

    XeTeX extends this convention with `^^^^` for four-digit Unicode characters.

-   Added support for more TeX primitives, including `\string`, `\csname`, `\endcsname`, `\obeyspaces`

-   Improved the handling of parameters (e.g. `#1`) to more accurately match the TeX behavior
    (previously parameters could only substitute for an entire argument, i.e. `{#1}`).
    They are now handled by replacing their value with their corresponding tokens.

-   Added support for `\laplace` and `\Laplace` symbols

### Bug Fixes

-   **#469** The keyboard layout on Linux was not detected
    correctly, resulting in some keys (such as arrows and backspace) not working correctly.

-   Integers in a Latex stream would not always be parsed
    correctly. As per the TeXBook, an integer can be preceded by an arbitrary number
    of "+", "-" or whitespace characters, so `\char -+ +- "4A` is valid and
    equivalent to `\char"4A`

-   Integers in a latex stream specified with a backtick (
    "alphabetic constant") would not be parsed correctly. Now `` \char`A `` gives the
    expected result (`A`).

-   Consecutive whitespace where not always coalesced.

-   The bounding box of the initial selection (before the 'first' atom was inserted) was incorrect.

-   The sizing commands (`\huge`, `\small`, `\tiny`, etc...) should not apply in 'math' mode.

## 0.52 (2020-05-23)

### New Feature

-   Support for [Trusted Types](https://w3c.github.io/webappsec-trusted-types/dist/spec/).

    A new option in `Config`, `createHTML`, is called before injecting HTML
    into the page, providing an opportunity to sanitize the markup according
    to a policy set by the host

### Improvements

-   Move some of the Mathematica inspired command (e.g. `\differentialD`,
    `doubleStruckCapitalN`, etc...) to be macros instead of built-in commands.
    This will allow them to be properly expanded during copy/paste operations
    for improved interoperability

-   When an invalid keybinding is encountered, the `onError` listener is now
    invoked with an erorr code of `invalid-keybinding`

-   Added support for German keyboard layout.

### Bug Fixes

-   The Undo and Redo button in the virtual keyboard did not change their
    state appropriately given the state of the undo stack.

-   'overunder': The superscript and subscript after an 'overunder' atom
    (e.g. `\overbrace`) did not display correctly (above or below the brace).
    The 'overunder' atom would also not display correctly if the width of
    the atom was below a minimal threshold.

## 0.51.0 (2020-05-19)

### New Features

-   **#450** Custom keybindings. A keybinding (also called keyboard shorcut)
    associate a keystroke combination on a physical keyboard with a command.
    Mathlive previously had some built-in keybindings, but now they can be
    extended or replaced.

    See `config.keybindings` and `Keybinding`

-   Added `setKeyboardLayout()` and `setKeyboardLayoutLocale()` functions to
    customize the current physical keyboard layout

### Improvements

-   **#461** The array editing commands only worked in math mode. They now apply
    in text mode as well

-   **#459**: Add a placeholder for incomplete commands, for example entering
    `\frac` in command mode

-   Added some missing commands: `deleteNextChar`, `deletePreviousChar`,
    `deleteNextWord`, `deletePreviousWord`, `deleteToGroupStart`, `deleteToGroupEnd`,
    `deleteToMathFieldEnd`, `moveToSubscript`, `applyStyle`, `toggleVirtualKeyboard`,
    `hideVirtualKeyboard`, `showVirtualKeyboard`

-   In some cases, the top of the placeholder character could be cut off

### Bug Fixes

-   The Read Aloud feature would not work when a Neural Engine AWS voice
    was used (such as Joana or Matthew)

-   In the Vue wrapper, the `onKeystroke` handler would error

-   Styling (applying color, style) was disabled. This also affected mode change
    (i.e. alt+= to switch between text and math mode)

-   After completing a command in command mode (i.e. pressing the return key), the mode did not switch not math mode and remained in command mode.

## 0.50.8 (2020-05-13)

### Improvements

-   The Symbols keyboard is now a top-level keyboard. Previously it was accessible
    only from the Roman keyboard
-   Added some standard Latex commands: `\inf`, `\Pr`, `\liminf`, `\limsup`
-   Added inline shortcuts for some commands: `sinh`, `cosh`, `sec`, `csc`,
    `cot`, `arcsin`, `arccos`, `arctan`
-   When generating Latex output, only insert spaces when necessary (i.e. after
    commands that are followed by a letter). Conversely, _always_ generate the space
    when necessary (`\rbrack a` would generate `\rbracka`)
-   Minor rendering performance improvement

### Bug Fixes

-   The absolute value character "|" (and other small delimiters) would be
    displayed in the wrong font (and too small)

-   The absolute value key from the virtual keyboard would
    insert '|#@|'

-   The 'sqrt' key from the virtual keyboard or keyboard shortcut
    (option+V) would do nothing. The problem affected any inline shortcut or key
    that included a '#0' argument when there was no selection

-   Fixed an issue with long inline shortcuts that could trigger text mode
    (e.g. 'arcsin') and never apply the inline shortcut

-   Do not trigger smart mode conversion with arrow keys

-   Fixed an issue on iOS 12 and Firefox/Android where the Mathfield could not be
    focused (fix contributed by (https://github.com/beneater)

## 0.50.7 (2020-05-11)

-   **Fix #448**: Fix an issue where the "^" keyboard shortcut would not work

## 0.50.6 (2020-05-11)

-   Fix date stamping of declaration files

## 0.50.5 (2020-05-10)

-   **Fix #311** Before making a build, check the correct version of node and npm
    are installed
-   Make the build system work better on Windows
-   Do not update /dist on each push
-   When using a UMD module, do not export 'default'

## 0.50.4 (2020-05-09)

### Bug Fixes

-   **Fix #444** The "x^2" key in the virtual keyboard did not work as expected.

### Improvements

-   Updated the build system to automatically add the lastest entry from the
    CHANGELOG to the GitHub release note.

## 0.50.3 (2020-05-08)

### New Features

-   Added a `MathLive.version` string

## 0.50.2 (2020-05-07)

### Bug Fixes

-   Fixed an issue with rendering of MathML

### Improvements

-   Added additional contextual information to the parser error message. Detect
    more errors.

### Breaking Change

-   Renamed `config.error` to `config.onError` for consistency with the other
    listeners.

### New Feature

## 0.50.1 (2020-05-06)

### New Feature

-   A new option, `config.error` can be used to catch errors while parsing Latex.

    This is invoked both for the initial content of the mathfield, when the
    content of the mathfield is changed programmatically, and when the user
    pastes latex content in the field.

    An error code will indicate the problem encountered, but the parsing will
    attempt to recover, in keeping with the previous behavior.

### Bug Fixes

-   Fixed an issue where the alphabetic 'sans' keys on the virtual keyboard output blackboard.
-   Fixed an issue where the `\mleft.` and `\mright.` commands would not be rendered correctly (or propertly converted to MathASCII). (https://github.com/benetech/MathShare/issues/1182)

## 0.50 (May 4, 2020)

### Highlights

-   **Maintenance**: Migration to TypeScript
-   **Maintenance**: New math variant (bold, italic, etc...) subsytem matches LaTeX more closely
-   **Maintenance**: Reduced code size
-   **New feature**: Verbatim Latex
-   **New feature**: `Mathfield.getConfig()`

### New Features

-   **"Verbatim Latex"**: the Latex provided as input (for example with `insert()`)
    is preserved as long as it's not edited. Previously, the Latex would be
    normalized on input, and the output would not match character
    for character, even though it produced equivalent Latex code. For example,
    extra spaces could be inserted, and the order of subscript and superscript was
    not preserved.

    Now, the input Latex is preserved until
    editing operations cause it to be modified. This also means that the arguments
    of macros are never modified (since the macros are not editable) and will be
    returned exactly as input (they were normalized before).

-   New **`letterShapeStyle`** configuration setting to control which letters are automatically italicized, according to four popular styles:

    | `letterShapeStyle` | xyz | ABC | αβɣ | ΓΔΘ |
    | -----------------: | --- | --- | --- | --- |
    |              `iso` | it  | it  | it  | it  |
    |              `tex` | it  | it  | it  | up  |
    |           `french` | it  | up  | up  | up  |
    |          `upright` | up  | up  | up  | up  |

    **(it)** = italic\
    **(up)** = upright

    The default letter shape style is `auto`: if the system locale is "french", the `french` style will be used, `tex` otherwise. The previous behavior was to always use `tex` style lettershape.

-   New `Mathfield.getConfig()` method which gives access to the current configuration settings.

    It can be invoked in three different ways:

    -   `mf.getConfig()`: return a `MathfieldConfig` object will the values for all
        the configuration options filled-in.
    -   `mf.getConfig('letterShapeStyle')`: return the current value of the
        `letterShapeStyle` option
    -   `mf.getConfig(['smartMode', 'smartFence'])`: return an object with the
        values of the `smartMode` and `smartFence` filled in.

    Note that `getConfig()` may return a different value immediately after `setConfig()`
    was invoked: `getConfig()` returns a "resolved" value, so for example:

    ```javascript
    mf.setConfig({ letterShapeStyle: 'auto' });
    console.log(mf.getConfig('letterShapeStyle')); // prints 'tex'
    ```

*   An example (`examples/test-cases`) with some test cases was added, including LaTeX output screenshots for comparison.

*   Re-done the font selection sub-system. Internally, it's now cleaner and
    easier to follow, and also closer to the LaTeX implementation. In particular,
    in math mode, the styling directives are exclusive, except for `\mathsymbol`,
    which matches the TeX behavior.

*   When a character variant (for example using `\mathbb`) is not available in
    the font repertoire, convert to Unicode and fallback to the system font. This
    allows `\mathbb{1}` to correctly output 𝟙.

*   Added support for `\ensuremath` command

*   Added the `\imageof` ⊷ and `\originalof` ⊸ symbols

### Code Maintenance

#### Codebase Migrated to Typescript

This does not impact the bundled library, which is still transpiled JavaScript from the TypeScript sources and which can be used either with a JavaScript or TypeScript based project.

The migration did not result in changes to the public API which remains backward compatible with previous versions. However, new declaration files (`*.d.ts`) for TypeScript are available. They are more detailed (and accurate) than the previous ones which were generated from JSDoc comments.

The migration was done by hand for the entire code base (35 kloc). Type information was provided for all the data structures and function signatures.

While this does not affect the external users of MathLive (the API and functionality remains the same), this has resulted in several bugs being found by the compiler through static analysis. For example, the `onUndoStateWillChange()` handler was never invoked because of this statement:

```javascript
if (options && options.onUndoStateWillChange === 'function') {
    options.onUndoStateWillChange();
}
```

instead of:

```javascript
if (options && typeof options.onUndoStateWillChange === 'function') {
    options.onUndoStateWillChange();
}
```

The TypeScript compiler correctly flagged this error.

This migration will make the ongoing maintenance and development of the codebase much easier.

#### Codebase Refactoring

Concurrently to the migration to TypeScript, and thanks to the increased clarity and confidence brought in with static typing and code analysis tools, the code has been modularized and reorganized as follow. The codebase previously consisted of several large monolithic source files, some of which were in excess of 4,500 loc.

They have been broken up as follow:

-   `core/atom.js` →
    -   `atom-array.ts`
    -   `atom-accent.ts`
    -   `atom-box.ts`
    -   `atom-enclose.ts`
    -   `atom-genfrac.ts`
    -   `atom-leftright.ts`
    -   `atom-line.ts`
    -   `atom-op.ts`
    -   `atom-overunder.ts`
    -   `atom-surd.ts`
    -   `atom-to-latex.ts`
    -   `atom-utils.ts`
    -   `atom.ts`
-   `core/definitions.js` →
    -   `definitions-accents.ts`
    -   `definitions-enclose.ts`
    -   `definitions-environments.ts`
    -   `definitions-extensible-symbols.ts`
    -   `definitions-functions.ts`
    -   `definitinos-styling.ts`
    -   `definitions-symbols.ts`
    -   `definitions-utils.ts`
    -   `definitions.ts`
-   `core/parser.js` →
    -   `parser.ts`
    -   `modes.ts`
    -   `modes-utils.ts`
    -   `modes-math.ts`
    -   `modes-text.ts`
    -   `modes-command.ts`
-   `editor-mathlist.js` →
    -   `model.ts`
    -   `model-utils.ts`
    -   `model-styling.ts`
    -   `model-smartfence.ts`
    -   `model-selection.ts`
    -   `model-listeners.ts`
    -   `model-insert.ts`
    -   `model-delete.ts`
    -   `model-commands.ts`
    -   `model-command-mode.ts`
    -   `model-array.ts`
    -   `model-array-utils.ts`
-   `editor-mathfield.js` →
    -   `a11y.ts`
    -   `autocomplete.ts`
    -   `commands.ts`
    -   `config.ts`
    -   `speech.ts`
    -   `speech-read-aloud.ts`
    -   `undo.ts`
    -   `mathfield.ts`
    -   `mathfield-virtual-keyboards.ts`
    -   `mathfield-utils.ts`
    -   `mathfield-styling.ts`
    -   `mathfield-smartmode.ts`
    -   `mathfield-render.ts`
    -   `mathfield-pointer-input.ts`
    -   `mathfield-keyboard-input.ts`
    -   `mathfield-commands.ts`
    -   `mathfield-clipboard.ts`
    -   `mathfield-buttons.ts`

Again, this is an internal change that will have no impact for external users of the MathLive library, but it will be contribute to improving the maintainability and velocity of the project.

#### Other Code Maintenance

-   Updated font binaries
-   Rewrote grapheme splitter in TypeScript. As a result, code size reduced by 113Kb (!).
-   Switched to `jest` as a test runner.

### Bug Fixes

-   **Fix #285**: The initial content of the mathfield was considered part of the
    undo stack, that is, typing command+Z before making any editing operations
    would make the initial content disappear.
-   **Fix #236**: An initially empty field had no visible caret until it had focused,
    then blurred, then focused again.
-   **Fix #438**: MathLive did not behave correctly when inside a shadow DOM
-   **Fix #436**: When `smartFence` was on, applying an inline shortcut before
    the closing parent of a paren group that had been inserted as a pure fence
    (not a `\left\right` group) the parens would get (incorrectly) promoted
    to a `\left\right` group, and the shortcut would be inserted outside of the
    paren.
-   **Fix #435**: Virtual keyboard after a JSON-based virtual keyboard would not
    display correctly.
-   **Fix #417**: The "International Backslash" (labeled `><` on a german keyboard)
    would incorrectly trigger the command mode.
-   **Fix #416**: With `smartFence` on, braces around a fraction would disappear,
    e.g. typing "(1/2" would result in "1/2"
-   **Fix #415**: `toASCIIMath()` would fail when the mathfield was empty

-   **Fix #393**: some characters in a `\operatorname` command, including `-` and `*`, were not displayed correctly (they should display as if in text mode, not in math mode, and the correct glyphs are different between the two modes)

-   **Fix #395**: re-implemented how macros handle their arguments. They would previously
    parse their argument using the current parseMode. This is incorrect. The parseMode
    cannot be determined until the macro has been expanded and the arguments substituted.
    The parsing of the macros arguments is now deferred until after the macro has been
    expanded. Additionally, it wasn't previously possible for arguments to macros
    to contain other arguments. This is now allowed.

-   **Fix #395 (bis)**: Properly output Latex for macros when using 'latex' and 'latex-expanded' formats.

-   Fixed numerous issues with LaTeX round-tripping. For example, `\mathfrak{C}`,
    `\boldsymbol{\sin\theta}`,

-   If the `\text` command included a `&`, the content following the `&` would be ignored.

-   The `align*` environment was not handled correctly and displayed an extra gap between columns.

-   The math styling commands did not behave properly. For example:\
    \
    `\mathbf{\sin \alpha} + \mathit{\cos \beta} + \mathbf{\tan x} + \boldsymbol{\sin \gamma}`

|       | before       | after       |
| ----- | ------------ | ----------- |
| alpha | bold upright | italic      |
| cos   | italic       | upright     |
| tan   | bold         | roman       |
| gamma | bold upright | bold italic |

-   Related to the above, but worth noting separately, `\mathbf{\alpha}` should
    render as normal italic: the `\mathbf` command does not apply to lowercase
    greek letters. The command _does_ apply to uppercase greek letters. This is an artifact of the TeX font encoding, but the behavior is preserved for compatibility with TeX.

-   The `\textcolor` command did not apply to large symbols, such as `\sum`

-   Correctly output LaTeX for infix operators such as `\atopwithdelims`

-   Correctly output unicode characters in the astral plane, e.g. `\unicode{"1F468}`

-   Fixed an issue were consecutive calls to set the content of the mathfield could result in some spurious characters inserted at the beginning of the field.

### Breaking Change

-   The signature of the `latexToMarkup()` function has changed.\
    Instead of a
    style and format, the second argument is an option object. The style can be
    specified with a `mathstyle` property, the format with a `format` property.
    A new `letterShapeStyle` property can also be specified.

    -   Before: `MathLive.latexToMarkup(formula, 'displaystyle')`
    -   After: `MathLive.latexToMarkup(formula, { mathstyle: 'displaystyle' });`

-   The 'command' virtual keyboard is no longer displayed by default. The layout
    for this virtual keyboard has been deprecated and will be removed in a future
    version. This is a partial fullfilment of #270.

-   The `config.handleSpeak` and `config.handleReadAloud` hooks have been renamed `config.speakHook` and `config.readAloudHook` respectively

### Deprecated

-   The `overrideDefaultInlineShortcuts` is deprecated (still supported in this
    version, but will be removed in an upcoming one). Instead, to add to the default
    shortcuts, use:

```javascript
mf.setConfig({
    inlineShortcuts: {
        ...mf.getConfig('inlineShortcuts').inlineShortcuts,
        ...newShortcuts,
    },
});
```

## 0.35.0 (2020-03-24)

### New Features

-   **Extensible (stretchy) symbols**:

    **#126** (`\overgroup`, `\overrightarrow`, `\overleftrightarrow`), **#180** (`\xrightarrow`, `\xrightleftharpoons`), **#292** (`\widehat`, `\overbrace`, `\underbrace`), **#338** (`\vec`, `\bar`).

    This work has been made possible thanks to the financial support of a generous sponsor.

    It is now possible for a symbol with operands above or below, or for a decoration above or below an expression, to stretch (extend) so that its width will match the width of the operands or expression.

    These extensible symbols and decorations are important for some domains such as geometry and chemistry.

    This release introduces th following new commands:

    -   `\overrightarrow{base}`
    -   `\overleftarrow{base}`
    -   `\Overrightarrow{base}`
    -   `\overleftharpoon{base}`
    -   `\overrightharpoon{base}`
    -   `\overleftrightarrow{base}`
    -   `\overbrace{base}`
    -   `\overlinesegment{base}`
    -   `\overgroup{base}`
    -   `\underrightarrow{base}`
    -   `\underleftarrow{base}`
    -   `\underleftrightarrow{base}`
    -   `\underbrace{base}`
    -   `\underlinesegment{base}`
    -   `\undergroup{base}`
    -   `\xrightarrow[below]{above}`
    -   `\xleftarrow[below]{above}`
    -   `\xRightarrow[below]{above}`
    -   `\xLeftarrow[below]{above}`
    -   `\xleftharpoonup[below]{above}`
    -   `\xleftharpoondown[below]{above}`
    -   `\xrightharpoonup[below]{above}`
    -   `\xrightharpoondown[below]{above}`
    -   `\xlongequal[below]{above}`
    -   `\xtwoheadleftarrow[below]{above}`
    -   `\xtwoheadrightarrow[below]{above}`
    -   `\xleftrightarrow[below]{above}`
    -   `\xLeftrightarrow[below]{above}`
    -   `\xrightleftharpoons[below]{above}`
    -   `\xleftrightharpoons[below]{above}`
    -   `\xhookleftarrow[below]{above}`
    -   `\xhookrightarrow[below]{above}`
    -   `\xmapsto[below]{above}`
    -   `\xtofrom[below]{above}`
    -   `\xrightleftarrows[below]{above}`
    -   `\xrightequilibrium[below]{above}`
    -   `\xleftequilibrium[below]{above}`

    In addition, the following commands can now be used to represent stretchy accents:

    -   `\widehat{base}`
    -   `\widecheck{base}`
    -   `\widetilde{base}`
    -   `\utilde{base}`

-   Improved rendering and layout of `\enclose`

-   Improved layout of `overunder` atoms

-   Improved layout of `accent` atoms

-   Improved fidelity of styling commands (`\textup`, `\fontseries`, etc...). They are now closer to what LaTeX does, in all its wonderful weirdness (see https://texfaq.org/FAQ-2letterfontcmd). Added `\selectfont` command.

### Bug Fixes

-   **#371**: When clicking after the last element in the mathfield, always set the anchor to be the last element in the root, i.e. as if `moveToMathFieldEnd` had been performed. For example, if the content is "x^2", clicking after the end of the field will put the caret after the last element (not after the "2" in the superscript)

-   **#372**: Using an argument in a macro will result in the argument to be substituted without a group being inserted. Previously, `#1` with `ax` as a value for the first argument would have resulted in `{ax}`. This was noticeable when using the `x^2` key in the virtual keyboard: if the equation was `ab`, pressing that key resulted in `{ab}^2`. It now results in `ab^2`

-   Fixed an issue rendering some commands such as `\boxed` and others when in static mode. An over-agressive optimization would coalesce spans with no content, even though they may include important styling info.

-   Fixed the rendering of infix commands with arguments, e.g. `\atopwithdelims` and `overwithdelims`. The arguments of infix commands were incorrectly merged with the suffix.

-   Fixed inter-atom spacing of `overunder` atoms (they should space as `mord`)

### Code Maintenance

-   Re-factored the definitions of functions, symbols and environments which are now split in multiple files instead of being all contained in `core/definitions.js`

-   Re-factored and isolated the metadata about LaTex commands (frequency and category). This should reduce the amount of data carried by the core package. All the metadata is now in `definitions-metadata.js`. As a side effect, the examples displayed in the popover window might be less complete, but the removal of popover is on the roadmap.

-   Removal of default export for some modules. Need to complete it for all the remaining modules.

## 0.34.0 (2020-02-05)

### Bug Fixes

-   Fix #364: Some expressions containing placeholders, when inserted, would not have the placeholder selected. For example, when using the "differentialD" key in the virtual keyboard.
-   Fix #349:
    -   'latex-expanded' format no longer returns `\mleft` and `\mright`. This
        format is intended for inter-exchange with other TeX-compatible renderers
        and the `\mleft` and `\mright` commands are not widely deployed.
    -   The content exported to the clipboard is now surrounded by `$$` to more
        clearly indicate that the content is using TeX format.
    -   When pasting content that begins/ends with `$` or `$$`, assume LaTeX format
-   Fix keyboard shortcuts, e.g. "alt+(" or "alt+v"
-   Fix #354: The argument of `\operatorname` is of type 'math', not 'text'. This means that using the '\text' command inside the argument is valid and that spaces should be ignored by default (but the `~` character can be used to insert a space in that context).
-   Fix #282: Some keys from the virtual keyboards ('e', 'i') produce an incorrect input.
-   Fix #227: An operator (`\sin`) following some text is incorrectly considered
    to be part of the text.

### Features / Improvements

-   Documented `suppressChangeNotifications` options for `$insert()`
-   Document `config.smartMode` (#312)
-   The 'surd' (root) and 'leftright' (fences) elements now change color when the caret is inside their body. This helps distinguish the case where the caret position may be ambiguous, for example when it is either after the last element of the body of a 'surd' or the first element after the 'surd'.
-   #339: Read-only mode. Set the mode to read-only with `mf.$setConfig({readOnly: true})`. When this mode is activated, the formula can be selected (so it can be copied), but it cannot be modified by the user. Progammatic modification is still possible.

## 0.33 (2019-12-19)

### Bug Fixes

-   Fix #313. Text mode content is not output in MathML, speech and MathJSON (contribution by @NSoiffer)
-   Fix #275: Selection improvements (use centerpoint to calculate nearest atom) and make delimiters selection eligible.

## 0.32.3 (2019-10-29)

### Bug Fixes

-   Fix #286 `\mathbb{}`s are missing in the Latex output

## 0.32.2 (2019-09-24)

### Bug Fixes

-   Fixed an issue where some keys in the virtual keyboard would be unresponsive

## 0.30.1 (2019-07-30)

### Features / Improvements

-   Added Typescript type definition

## 0.30 (2019-07-18)

### Non-backward compatible changes

-   #157: Public APIs that don't start with `$` have been removed. If your code
    used any of these APIs, add a `$` in front of their name. See #157 for the
    complete list.

### Features / Improvements

-   #231: `smartMode` now supports Greek (the language). Also, Greek localization.
-   Don't display i-beam cursor over non-interactive content
-   Use CSS class `.ML__smart-fence__close` to style closing smart fence
-   Added speech support for text mode and units (contributed by @NSoiffer)

### Bug Fixes

-   Fixed an issue where clicking past the end of the equation would select the
    numerator or denominator if the last element was a fraction, instead of place
    the cursor after the fraction (regression)
-   Removed dependency on open-cli
-   #220 Fixed an issue where tabbing out of a mathfield would break command mode and some functions
-   #209, #214, #211 et. al. Improvements to SSML support and karaoke mode contributed by @NSoiffer
-   #217 Fixed an issue with parentheses in numerator of fractions
-   #212: Fix round-tripping of `\mathbb`
-   #194: When using the virtual keyboard, interpolate `#@`
-   Fixed an issue where "(" was incorrectly gobbled as argument to a fraction
-   Fixed an issue where smartFence off was ignored
-   #202: use numeric character references instead of named entities in MathML output

## 0.29.1 (2019-05-19)

### Bug fixes

-   #201: the popover button was not responsive
-   #195: (partial fix) improve support for Edge (still requires Babelization)
-   Fixed an issue while dragging to select across elements of different depths
-   Fixed issue with smartMode for expressions including "x^2", "xyz" and "\pi"
-   Fixed an issue with styling, where the Latex output could sometimes include the non-existent `\mathup` command. The correct command is `\upshape`
-   Fixed issues with enclose layout
-   Avoid triggering spurious notifications while inserting an inline shortcut

## 0.29 (2019-05-09)

### Major New Features

-   Scrollable mathfield. The mathfield now behaves like a text area: the content
    that does not fit withing the bounds of the mathfield will not overflow
    but will be scrollable. The scrolling can be done using the mouse wheel or
    trackpad gestures, or by dragging while selecting. The AP

### Improvements

-   When smartFence is on, and a new smart fence is inserted (by typing
    `(` for example), the closing 'phantom' fence would be displayed immediately
    after the opening fence. The closing fence will now be inserted after
    the end of the expression.
-   The heuristics for determining implicit arguments, for example the implicit
    numerator when typing `/` have been improved. For example, typing `/` after
    `3 + 2sin x` will result in `3 + (2sin x)/(...)` instead of `3 + sin (x)/(...)`.
-   When `config.removeExtraneousParentheses` is true (default), if a frac is
    inserted inside parentheses, the parens will be removed. So, if a `/` is typed
    after `1` in `(1)` it will become `1/(...)`.
-   When smartMode is on, textual operators are eligible for conversion to text.
    Previously, if an inline shortcuts for `rad` was defined to `\operatorname{rad}`
    and 'radius' was typed, only `ius` would be turned to text.
-   Smartmode is now applied when there is a selection. That is, if some text is
    selected and the `/` is pressed the selection will become the numerator. Previously
    the selection was deleted and replaced with an empty fraction
-   Improved layout of surds, particularly when the surd is empty
-   Made `\mathbb{}` et al. apply to the argument only, and not affect the style
    of following characters. Previously, if a `\mathbb{R}` was inserted, the following
    typed character would also be in Blackboard style.
-   Improved build system on Windows. That is, it now works.
-   Merge speak and readAloud APIs into one (contribution from Neil. Thanks Neil!)
-   Switched to using `npm ci` for CI builds. Even for local builds,
    it is recommended to use `npm ci` to ensure the correct version of the dependencies
    are installed.
-   In smartMode, the currency symbols are handled better. "One apple is $3.14" 
will result in the "$" being in math mode.
-   Switching to/from command mode will not suppress smart mode.

### Bug fixes

-   Fixed a crash when using smartFence with `sin(x^2/`
-   Fixed `alt+=` keyboard shortcut on Windows.
-   Fixed some layout issues with `box` and `enclose`
-   Smart Fences will now work when invoked from the virtual keyboard.
-   Fixed #177: custom localization strings are now handled correctly.
-   Fixed some issues toggling style when selection is empty.

## 0.28 (2019-04-22)

This release contains some small bug fixes and improvements.

-   Reduced Node version required (for dev builds) to Node LTS
-   Fixed some issues with focus state of mathfields, particularly with multiple mathfields on a page
-   Fixed an issue with some keys (such as /) on