Migration Guide

As of KaTeX 1.0, we've changed how MacroExpander and Parser work in order to close some gaps between KaTeX and LaTeX and therefore there may be breaking changes.

Macro arguments

Tokens will not be expanded while parsing a macro argument. For example, \frac\foo\foo, where the \foo is defined as 12, will be parsed as \frac{12}{12}, not \frac{1}{2}12. To expand the argument before parsing, \expandafter can be used like \expandafter\frac\foo\foo.

\def

\def no longer accepts a control sequence enclosed in braces. For example, \def{\foo}{} no longer works and should be changed to \def\foo{}.

It also no longer accepts replacement text not enclosed in braces. For example, \def\foo1 no longer works and should be changed to \def\foo{1}.

\newline and \cr

\newline and \cr no longer takes an optional size argument. To specify vertical spacing, \\ should be used.

\cfrac, \color, \textcolor, \colorbox, \fcolorbox

They are no longer allowed as an argument to primitive commands, such as \sqrt (without the optional argument) and super/subscript. For example, \sqrt\textcolor{red}{x} no longer works and should be changed to \sqrt{\textcolor{red}{x}}.