chunk

rubyonrails-talk
1

Hi,

I am a beginner in ruby and It try to undertand the concept of "enum.chunk" in particular these 2 exemples (Index of Files, Classes & Methods in Ruby 3.1.2 (Ruby 3.1.2) classes/Enumerable.html#M003131)

" open("/usr/share/dict/words", "r:iso-8859-1") {|f|     f.chunk {|line| line.ord }.each {|ch, lines| p [ch.chr, lines.length] } "

and " sep = "-"*72 + "\n"   IO.popen("svn log README") {|f|     f.chunk {|line|       line != sep || nil     }.each {|_, lines|       pp lines     }   } "

What do those mean ? I can't understand the way it works...

Best regards,

Jr

2

Hi,

I am a beginner in ruby and It try to undertand the concept of "enum.chunk" in particular these 2 exemples (RDoc Documentation classes/Enumerable.html#M003131)

it groups consecutive elements according to the value of the block you supply, and returns an array of arrays, one for each group

" open("/usr/share/dict/words", "r:iso-8859-1") {|f| f.chunk {|line| line.ord }.each {|ch, lines| p [ch.chr, lines.length] } "

this opens a dictionary file, and then groups by the first character of each line, before outputting the size of each group (i.e. the number of words in the dictionary file beginning with that letter)

Fred

3

result = [2, 4, 1, 3, 5, 6, 8].chunk do |num|   num.even? end

result.each do |even_result, a_chunk|   p [even_result, a_chunk] end

--output:-- [true, [2, 4]] [false, [1, 3, 5]] [true, [6, 8]]