golf: tabs to bullets

[Martin DeMello]

Given:
an outline list, with each line indented by a series of tabs
a list of bullets (assume a circular list, for simplicity)

Write a function that replaces every tab with two spaces, except for
the last one, which is replaced by a bullet.

example:

input file:
foo
\t bar
\t \t baz
\t \t \t hello
\t \t world

bullets: %w(* - o x)

output (view in fixed width):
foo
* bar
- baz
o hello
- world

martin

 

[Martin DeMello]

Given:
an outline list, with each line indented by a series of tabs
a list of bullets (assume a circular list, for simplicity)

Write a function that replaces every tab with two spaces, except for
the last one, which is replaced by a bullet.

Code is worth a thousand descriptions:

#!/usr/bin/ruby

file = ARGV[0]
MARKERS = "*-ox".split(//)

def bullet(n)
MARKERS[n % MARKERS.length]
end

IO.foreach(file) {|line|
a = line.gsub(/^\t+/, "")
n = line.length - a.length - 1
replace = n == -1 ? "" : " "*(n)+ bullet(n) + " "
out = line.gsub(/^\t+/, replace)
puts out
}

martin

 

[James Gray]

Given:
an outline list, with each line indented by a series of tabs
a list of bullets (assume a circular list, for simplicity)

Write a function that replaces every tab with two spaces, except for
the last one, which is replaced by a bullet.

example:

input file:
foo
\t bar
\t \t baz
\t \t \t hello
\t \t world

bullets: %w(* - o x)

output (view in fixed width):
foo
* bar
- baz
o hello
- world

I didn't really golf it, but my answer is:

#!/usr/bin/env ruby -wKU

input = <<END_INPUT
foo
\t bar
\t \t baz
\t \t \t hello
\t \t world
END_INPUT

bullets = %w[* - o x]
input.gsub!(/^(\t ?)+/) do |indent|
tabs = indent.count("\t") - 1
" " * tabs + bullets[tabs] + " "
end

puts input

__END__

James Edward Gray II

 

[Martin DeMello]

I didn't really golf it, but my answer is:

You have a point - I wasn't looking for golf so much as for neat
and/or offbeat approaches to the problem of counting the tabs.

martin

 

[David A. Black]

Hi --

You have a point - I wasn't looking for golf so much as for neat
and/or offbeat approaches to the problem of counting the tabs.

Darn, I took you literally

def t(s)b='*-ox';s.map{|l|c=l.count("\t")
(c-1).times{l.sub!(/\t/,' ')}
l.sub(/\t/,b[c-1,1])}end

t(some_string)

(Thanks to JEG2 for reminding me of count, which I had hypercorrected
in my mind into thinking only existed in 1.9 because of Array#count



David

--
Rails training from David A. Black and Ruby Power and Light:
ADVANCING WITH RAILS April 14-17 New York City
INTRO TO RAILS June 9-12 Berlin
ADVANCING WITH RAILS June 16-19 Berlin
See http://www.rubypal.com for details and updates!

 

[Joel VanderWerf]

A slightly different approach (count the tabs once!), starting from
James's code:

input = <<END_INPUT
foo
\t bar
\t \t baz
\t \t \t hello
\t \t world
END_INPUT

bullets = %w[* - o x]

h = Hash.new {|h, k|
bullet = bullets[(k.count("\t")-1) % bullets.size]
h[k] = k.gsub(/(\t )(?=\t )/, " ").sub(/\t/, bullet)
}

input.gsub!(/^(\t ?)+/) do |indent|
h

end

puts input

__END__

foo
* bar
- baz
o hello
- world​

 

[Gordon Thiesfeld]

Similar to Joel's approach...

#bullets.rb
h={}
%w(\ * - o x).each_with_index{|b, i| h["\t" * i]= " " * i + "#{b} " }
puts gets.gsub(/^(\t*)/){ h[$1]} until $stdin.eof?

C:\ruby\scripts\>cat input_file | ruby bullets.rb
foo
* bar
- baz
o hello
- world

 

[Gordon Thiesfeld]

Similar to Joel's approach...

#bullets.rb
h={}
%w(\ * - o x).each_with_index{|b, i| h["\t" * i]= " " * i + "#{b} " }
puts gets.gsub(/^(\t*)/){ h[$1]} until $stdin.eof?

C:\ruby\scripts\>cat input_file | ruby bullets.rb


foo
* bar
- baz
o hello
- world

Except it was broken. I'll try it again.

#bullets.rb
h={''=>''}
%w(* - o x).each_with_index{|b, i| h["\t" * (i+1)]= "#{' ' * i}#{b} " }
puts gets.gsub(/^(\t*)/){ h[$1] } until $stdin.eof?

 

[Joel VanderWerf]

h[k] = k.gsub(/(\t )(?=\t )/, " ").sub(/\t/, bullet)

a little more robust:

h[k] = k.gsub(/(\t ?)(?=\t)/, " ").sub(/\t/, bullet)

 

[ara howard]

Given:
an outline list, with each line indented by a series of tabs
a list of bullets (assume a circular list, for simplicity)

Write a function that replaces every tab with two spaces, except for
the last one, which is replaced by a bullet.

example:

input file:
foo
\t bar
\t \t baz
\t \t \t hello
\t \t world

bullets: %w(* - o x)

cfp2:~ > cat a.rb
DATA.read.gsub(%r/(?:\t\ ?)+/){|s|' '*(n=s.count("\t")-1)+%w(* - o x)
[n]+' '}.display

__END__
foo
bar
baz
hello
world


cfp2:~ > ruby a.rb
foo
* bar
- baz
o hello
- world



a @ http://drawohara.com/

 

[David A. Black]

Hi --

Given:
an outline list, with each line indented by a series of tabs
a list of bullets (assume a circular list, for simplicity)

Write a function that replaces every tab with two spaces, except for
the last one, which is replaced by a bullet.

example:

input file:
foo
\t bar
\t \t baz
\t \t \t hello
\t \t world

bullets: %w(* - o x)

cfp2:~ > cat a.rb
DATA.read.gsub(%r/(?:\t\ ?)+/){|s|' '*(n=s.count("\t")-1)+%w(* - o x)[n]+'
'}.display

I don't think that does the two-space thing:

david-blacks-macbook:hacking dblack$ cat ara.rb
<<EOM.gsub(%r/(?:\t\ ?)+/){|s|' '*(n=s.count("\t")-1)+%w(* - o x)[n]+'
'}.display
\t\t\ta
\t\tb
\t\t\t\tc
EOM
david-blacks-macbook:hacking dblack$ ruby ara.rb
o a
- b
x c

Then again, mine didn't either....


David

--
Rails training from David A. Black and Ruby Power and Light:
ADVANCING WITH RAILS April 14-17 New York City
INTRO TO RAILS June 9-12 Berlin
ADVANCING WITH RAILS June 16-19 Berlin
See http://www.rubypal.com for details and updates!

 

[David A. Black]

Hi --

Hi --



Darn, I took you literally

def t(s)b='*-ox';s.map{|l|c=l.count("\t")
(c-1).times{l.sub!(/\t/,' ')}

Whoops, that should be ' ' (two spaces).


David

--
Rails training from David A. Black and Ruby Power and Light:
ADVANCING WITH RAILS April 14-17 New York City
INTRO TO RAILS June 9-12 Berlin
ADVANCING WITH RAILS June 16-19 Berlin
See http://www.rubypal.com for details and updates!

 

[ara howard]

Then again, mine didn't either....

neither did the OPs - my gives back the sample data, which actually
required one - easy to change though.

a @ http://codeforpeople.com/

 

[David A. Black]

Hi --

neither did the OPs - my gives back the sample data, which actually required
one - easy to change though.

I'm seeing it differently; I see Martin's like this:

foo
* bar
- baz
o hello
- world

and yours like this:

foo
* bar
- baz
o hello
- world

That's what I was referring to.


David

--
Rails training from David A. Black and Ruby Power and Light:
ADVANCING WITH RAILS April 14-17 New York City
INTRO TO RAILS June 9-12 Berlin
ADVANCING WITH RAILS June 16-19 Berlin
See http://www.rubypal.com for details and updates!

 

[ara howard]

I'm seeing it differently; I see Martin's like this:

oh yeah - interesting. the fix:

cfp2:~ > cat a.rb
DATA.read.gsub(%r/(?:\t\ ?)+/){|s|' '*(n=s.count("\t")-1)+%w(* - o x)
[n]+' '}.display

__END__
foo
bar
baz
hello
world


cfp2:~ > ruby a.rb
foo
* bar
- baz
o hello
- world


a @ http://codeforpeople.com/

 

[Jean-François Trân]

Darn, I took you literally

def t(s)b=3D'*-ox';s.map{|l|c=3Dl.count("\t")
(c-1).times{l.sub!(/\t/,' ')}
l.sub(/\t/,b[c-1,1])}end

t(some_string)

You forgot the modulo :

with c =3D l.count("\t')-1, it gives :

def t(s)b=3D'*-ox';d=3Db.size;s.map{|l|c=3Dl.count("\t")-1
c.times{l.sub! /\t/,' '}
l.sub /\t/,b[c%d,1]}end

input :

input =3D <<END_INPUT
foo
\t bar
\t \t baz
\t \t \t hello
\t \t \t \t ciao
\t \t \t \t \t bye
\t \t \t \t \t \t konnichiwa
\t \t world
END_INPUT

James has also forgotten :

bullets =3D %w[* - o x]
length =3D bullets.size
input.gsub!(/^(\t ?)+/) do |indent|
tabs =3D indent.count("\t") - 1
" " * tabs + bullets[tabs%length] + " "
end

-- Jean-Fran=E7ois.

 

[William James]

Given:
an outline list, with each line indented by a series of tabs
a list of bullets (assume a circular list, for simplicity)

Write a function that replaces every tab with two spaces, except for
the last one, which is replaced by a bullet.

example:

input file:
foo
\t bar
\t \t baz
\t \t \t hello
\t \t world

bullets: %w(* - o x)

output (view in fixed width):
foo
* bar
- baz
o hello
- world

martin

bullets = %w(. * - o x)

"foo
\t bar
\t \t baz
\t \t \t hello
\t \t world
".each{|x| puts x.reverse.sub("\t",bullets[x.count("\t")]).
reverse.gsub("\t"," ") }

 

[Adam Shelly]

I'm seeing it differently; I see Martin's like this:

oh yeah - interesting. the fix:

cfp2:~ > cat a.rb
DATA.read.gsub(%r/(?:\t\ ?)+/){|s|' '*(n=s.count("\t")-1)+%w(* - o x)
[n]+' '}.display

__END__
foo
bar
baz
hello
world

(86 bytes of code)


Here's one that shaves 9 bytes of Ara's while adding 2 fixes to match
the original spec:
use modulo for a circular list of bullets, and take an input filename
from the command line, instead of imbedding it.

$><<$<.read.gsub(/(?:\t\ ?)+/){|s|' '*(n=s.chop.size-1)+'*-ox'[n%4].chr+' '}

(77 bytes)