:Re: Comments requested on noob code

[Robert L.]

Peter Seibel wrote:

> John Landahl <jo...@landahl.org> writes:
>
> > Peter Seibel wrote:
> >> Oh, and find-in-file has a bug, it's passing RACK instead of
> >> SORTED-RACK to MATCH-WORD. Dunno if it'll run faster or slower when
> >> you fix that but at least it'll be correct.
> >
> > I did fix that. And by the way, I tried it first without string-downcase
> > and it didn't make that big of a difference time/memory-wise.
>
> Okay, here's my best offer. Basically the same algorithm as your
> original but without all the needless list creation.
>
> (defun find-in-file (file-name rack)
> (with-open-file (in file-name)
> (loop for word = (read-line in nil nil) while word
> when (match-word word rack) collect word)))
>
> (defun match-word (word rack)
> (loop with tiles = (copy-seq rack)
> for char across word
> always (find char tiles :test #'char-equal)
> do (setf tiles (delete char tiles :test #'char-equal :count 1))))


MatzLisp (Ruby):

def match_word word, rack
rack = rack.dup
word.chars.all?{|c| rack.sub!(c,"")}
end

def find_in_file filename, rack
IO.readlines(filename).select{|word|
match_word( word.chomp, rack)}.
map(&:chomp)
end

t=Time.now;p find_in_file("words", "smug");Time.now - t

["g", "gum", "gums", "m", "mg", "ms", "mu", "mug", "mus", "s", "sg",
"sm", "smug", "su", "sum", "u", "us"]
==>0.75


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