Maybe dumb question, but...
I have not found anything like Array.resize, i.e.
a = [1,2]
a.resize(5) #=> [1,2,nil,nil,nil]
a.resize(5, 3) #=> [1,2,3,3,3]
I can use Array.fill, but
a.fill(3, a.size, a.size+2)
looks a bit ugly, not?
Moreover, if I want to resize to size lesser then array is, I need slice.
Why not to have all-purpose resize?
Victor.
Victor Shepelev a écrit :
Maybe dumb question, but...
I have not found anything like Array.resize, i.e.
a = [1,2]
a.resize(5) #=> [1,2,nil,nil,nil] a.resize(5, 3) #=> [1,2,3,3,3]
I can use Array.fill, but
a.fill(3, a.size, a.size+2)
looks a bit ugly, not?
Moreover, if I want to resize to size lesser then array is, I need
slice.Why not to have all-purpose resize?
Victor.
You may try :
a = [1,2]
a.fill(3, -1, 3) #=> [1,2,3,3,3]
So you may code yourself your resize :
class Array
def resize(new_size, value=nil)
if new_size < length
slice!(new_size, length)
else
fill(value, -1, new_size-length)
end
self
end
end
Pierre
Victor Shepelev wrote:
Maybe dumb question, but...
I have not found anything like Array.resize, i.e.
a = [1,2]
a.resize(5) #=> [1,2,nil,nil,nil]
a.resize(5, 3) #=> [1,2,3,3,3]I can use Array.fill, but
a.fill(3, a.size, a.size+2)
looks a bit ugly, not?
a = [1,2,3]
a += [nil] * 3
Moreover, if I want to resize to size lesser then array is, I need slice.
a = [1,2,3,4,5]
a[0..-3]
Ruby 1.9 supports Array#pop taking an integer
lopex
Pierre Barbier de Reuille wrote:
a = [1,2]
a.fill(3, -1, 3) #=> [1,2,3,3,3]
nope:
a = [1,2]
a.fill(3, -1, 3) #=> [1,3,3,3]
since -1 points to the last value in an array
lopex
Pierre wrote
So you may code yourself your resize :
class Array
def resize(new_size, value=nil)
if new_size < length
slice!(new_size, length)
else
fill(value, -1, new_size-length)
end
self
end
end
Yes, I can (in fact, I already did).
The question is more ideological than technical. Why not to have
Array#resize in standard library? It seems not very rational.
Pierre
Victor.
Hi --
Pierre wrote
So you may code yourself your resize :
class Array
def resize(new_size, value=nil)
if new_size < length
slice!(new_size, length)
else
fill(value, -1, new_size-length)
end
self
end
endYes, I can (in fact, I already did).
The question is more ideological than technical. Why not to have
Array#resize in standard library? It seems not very rational.
I think it might be because the size of an array isn't important if
the array just contains nils, because uninitialized values default to
nil anyway. And if you're adding non-nil elements to the array, then
the fact that the size changes is not really the main point; it's just
a side-effect of the operation, so referring to it as a "resize"
operation doesn't fit very well.
David
On Tue, 28 Mar 2006, Victor Shepelev wrote:
--
David A. Black (dblack@wobblini.net)
Ruby Power and Light, LLC (http://www.rubypowerandlight.com)
"Ruby for Rails" chapters now available
from Manning Early Access Program! Ruby for Rails
David wrote:
> The question is more ideological than technical. Why not to have
> Array#resize in standard library? It seems not very rational.I think it might be because the size of an array isn't important if
the array just contains nils, because uninitialized values default to
nil anyway. And if you're adding non-nil elements to the array, then
the fact that the size changes is not really the main point; it's just
a side-effect of the operation, so referring to it as a "resize"
operation doesn't fit very well.
Sounds reasonable.
I can tell when I stumbled upon need for __resizing__ aray: when tried to
use Array#transpose - it can't process
[
[1,2,3],
[1],
[1,2,3,4]
]
I think, it isn't sole case, when we can want having array of arbitrary
size.
David
Victor.