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Convert any source file to text

Problem

DrScheme saves some files in a binary format that is inconvenient upon occasion. For example, it's difficult to compare these files using 'diff'.

Solution

The following script converts any DrScheme source file to text.

save-as-text.ss

(unless (= (vector-length argv) 2)
  (error 'graphical-to-text "usage: <executable> <input-filename> <output-filename>"))

(define in-filename (vector-ref argv 0))
(define out-filename (vector-ref argv 1))

(define t (new text%))
(send t load-file in-filename)
(define f (new frame% (label "") (width 500) (height 500)))
(define ec (new editor-canvas% (parent f) (editor t)))
(send t save-file out-filename 'text)

To run it, say, under UNIX:

mred -fv save-as-text.ss

Discussion

• The script is a MrEd script, not a MzScheme script. This is because files saved in the binary format make direct reference to MrEd entities (e.g. snip% and its descendants). MzScheme can't make head or tail of these references. This script does not open any windows, but it must be run in a graphical environment.

• You could use MzScheme juju to make the script directly executable. I've chosen not to, in order to simplify the presentation.

Comments about this recipe

I've added this to the GettingStartedChapter, for want of anywhere to put it.

-- NoelWelsh - 24 Sep 2004

Contributors

-- JohnClements - 23 Sep 2004