,elegant

[Leslie Viljoen]

Hiya!

This function adds commas to a string after every three characters
so a number would be easier to read. It's kinda ugly though, and I can't
help thinking there'd be a elegant Why-esque one or two liner to do
this kind of thing - anyone care to improve it?


def add_commas(str)
return nil if str.class != String

ret = ""
len = str.length
i = len - 1
while i >= 0
ret = str.chr + ret
if ((len-i) % 3) == 0
ret = "," + ret
end
i -= 1
end
if ret[0].chr == ","
ret = ret[1..-1]
end
ret
end

 

[James Edward Gray II]

Hiya!

This function adds commas to a string after every three characters
so a number would be easier to read. It's kinda ugly though, and I
can't
help thinking there'd be a elegant Why-esque one or two liner to do
this kind of thing - anyone care to improve it?

Does this help?

http://rubyurl.com/EOi

James Edward Gray II

 

[Leslie Viljoen]

Does this help?

http://rubyurl.com/EOi

James Edward Gray II

I knew it! This kind of thing makes me crazy! I used to think I was a
good programmer!

 

[ara.t.howard]

Hiya!

This function adds commas to a string after every three characters
so a number would be easier to read. It's kinda ugly though, and I can't
help thinking there'd be a elegant Why-esque one or two liner to do
this kind of thing - anyone care to improve it?


def add_commas(str)
return nil if str.class != String

ret = ""
len = str.length
i = len - 1
while i >= 0
ret = str.chr + ret
if ((len-i) % 3) == 0
ret = "," + ret
end
i -= 1
end
if ret[0].chr == ","
ret = ret[1..-1]
end
ret
end

harp:~ > cat a.rb
def commafy s
s.to_s.reverse.scan(%r/.{1,3}/).join(',').reverse
end

p(commafy(''))
p(commafy('4'))
p(commafy('42'))
p(commafy('422'))
p(commafy('4242'))
p(commafy('42424'))
p(commafy('424242'))
p(commafy('4242424'))

harp:~ > ruby a.rb
""
"4"
"42"
"422"
"4,242"
"42,424"
"424,242"
"4,242,424"

if you want you can play with the pattern so the two reverses aren't needed...
but this is quicker to write ;-)

-a
--
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| ara [dot] t [dot] howard [at] noaa [dot] gov
| all happiness comes from the desire for others to be happy. all misery
| comes from the desire for oneself to be happy.
| -- bodhicaryavatara
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