[R6RS] data relevant to ticket #117

William D Clinger will at ccs.neu.edu
Sun Dec 10 10:59:59 EST 2006


To investigate ticket #117, "Bodies should be more widely
supported", I grepped through a little over 300,000 lines
of Scheme code, in 922 files.  I found 101 occurrences of
(let () ...), and 227 occurrences of (letrec ...).  Of
these 328 occurrences, 4 would have become unnecessary if
the proposal made by ticket #117 were adopted.  All 4 were
in cond clauses.

By the way, I found 95 instances of the following pattern,
or of its equivalent using letrec:

    (define x 
      (let ()
        (define ...) ...))

That suggests that allowing (define <variable> <body>)
might be about 25 times as useful as the proposal made
by ticket #117.

Will



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