* Returns a new options object with the same properties as "this". Properties * from "extension" will be copied to the new options object.

`acceptUnicodeChar = true` is only applicable if `replace` is set.

`acceptUnicodeChar = true` is only applicable if `replace` is set.

* Sets an arbitrary attribute on the span. Warning: use this wisely. Not * all browsers support attributes the same, and having too many custom

JsonResult 响应 json 结果

* Get the current value of a name, or `undefined` if there is no value. * * Note: Do not use `if (namespace.get(...))` to detect whether a macro

* Gets an attribute on a MathML node.

* Set the current value of a name, and optionally set it globally too. * Local set() sets the current value and (when appropriate) adds an undo

* Get a text or display version of this style.

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* Return the font metrics for this size.

* 只支持ID选择。

* Detect whether `name` has a definition. Equivalent to * `get(name) != null`.

* Main parsing function, which parses an entire input.

从队列中获取一项

* Return an options object with the given style. If `this.style === style`, * returns `this`.

* Sets an attribute on a MathML node. MathML depends on attributes to convey a * semantic content, so this is used heavily.

* Considers the current look ahead token as consumed, * and fetches the one after that as the new look ahead.