Doug Rowland has written the excellent Equation Service (ES), so that ordinary word processors can use pdfLaTeX to typeset mathematics. Here's how it works: type some LaTeX in your document, select it, choose ‘Typeset' from the ES menu and the LaTeX is replaced by the PDF of the typeset expression. That's really nice if you want to mix math equations into a word processed document. Plop Sigma in your document, select ‘Typeset' and you get a beautiful LaTeX typeset sigma.
One of the really funky features of ES is that it embeds the LaTeX source within the generated PDF; for some editors, such as that embedded in Mail.app, there's a round trip: select ‘Untypeset' from the ES menu, and the PDF is replaced by the LaTeX source, which can be edited again. Select the typeset sigma, select ‘Untypeset,' and you get back the Sigma for editing.
Now, having picked up a copy of iWork, I've started using Pages. Excellent, excellent, excellent. Word is out of my dock, and out of my life. I've tried using ES with Pages. The trip from LaTeX to PDF works a treat, but there's a problem when you select the embedded PDF and try to ‘Untypeset.' Nothing happens; that's because Pages produces another version of the PDF which does not have the embedded LaTeX source in it. No embedded source, no ‘Untypeset'.
Disappointing, eh? Well yes, but here's a workaround: select the PDF of the typeset LaTeX, open the Pages Inspector panel, switch to Metrics -- the small rule in the Inspector panel -- and the original PDF file is there at the top under File Info, complete with embedded LaTeX source. Drop it onto the ES application, and you can edit the source again in the ES source window.
Of course, it would be nice if Pages would preserve the PDF ...is there any chance, do you think?
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