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grep-foo (Score:2)

by triv (2745)

@sizes = grep {length $_ -> [1]} @sizes; Specifically, what is {length $_ -> [1]} doing?

From the docs:
Evaluates the BLOCK or EXPR for each element of LIST (locally setting $_ to each element) and returns the list value consist- ing of those elements for which the expression evaluated to true. In scalar context, returns the number of times the expression was true.

The most basic example is something like:
perl -e '@foo = grep { $_ } (1,0,undef); print "@foo\n"'

This goes though the list (1,

--

--
"Cake or Death!" .... "Cake please"
- Re:grep-foo (Score:1)
  
  by xenchu (4746) on 2004.02.04 9:46 (#28038) Homepage Journal
  
  Oh. Ow. Ouch! @size is not an array of file names but rather a line with file name, file size, etc. I might plead that I am a windows programmer but geez, even so, I should have realized that. My stumbling block was [1]. I couldn't see the relationship even knowing what -> was. Density^3. Thank you.
  
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