[texhax] A question with regards to align*

Toby Cubitt toby-dated-1208099527.b21406 at dr-qubit.org
Tue Apr 8 17:12:01 CEST 2008

Christian Hans Aastrup wrote:
> Hello there!
>
> I'm very happy to display mathematics in
>
> \begin{align*}
> ...
> \end{align*}
>
> and I'm wondering whether it is possible to make LaTeX read
>
> $$....$$ as \begin{align*} ... \end{align*}???

Probably...but not easy. You'll have to change the catcode of to make it into an active character (not too difficult, but requires familiarity with low-level TeX), then define macros that expand to the right thing depending on whether you're opening or closing the environment (no idea how :) The flexisym and breqn packages from the mh bundle (available on CTAN) might give you some pointers. It will undoubtedly be easier to define to be a smart short-cut that inserts \begin{align*} or \end{align*} as appropriate, assuming you're using a decent editor (e.g. emacs, vim, or something fairly programmable -- no flame wars about the definition of "decent", please :) If you were prepared to use $...$ instead of...\$, then it would
probably just be a case of (untested):


HTH,

Toby