require does accept ony word, which should be the name that has
to be required. Since duck typing is en vogue, is it a bad idea to
have require use something like this here instead?
require %w( pp English pathname fileutils abbrev pp digest/md5 yaml)
The reason I write this is because I quite often see this:
I don’t understand why this is considered cumbersome. Certainly it’s
more readable than looping over an array, and it’s not like this is
something you have to type a lot, or read a lot.
“I don’t understand why this is considered cumbersome. Certainly it’s
more readable than looping over an array, and it’s not like this is
something you have to type a lot, or read a lot.”
Hi there,
It becomes cumbersome if you do like 20 lines of requires.
Thanks to Jesse M… This is one of the
reason ruby rocks.
Sorry if I’ve missed something in an earlier post, but “require”
doesn’t even seem to like having more than one argument. However, if
it did, you could always use the “unarray” operator to do *%w( yaml
pp ) in order to get the effect of ‘yaml’, ‘pp’.
$ irb
irb(main):001:0> require *%w[ yaml pp ]
ArgumentError: wrong number of arguments (2 for 1)
from (irb):1:in require' from (irb):1 irb(main):002:0> require 'yaml', 'pp' ArgumentError: wrong number of arguments (2 for 1) from (irb):2:in require’
from (irb):2
irb(main):003:0> p %w( yaml pp )
[“yaml”, “pp”]
=> nil
irb(main):004:0> p *%w( yaml pp )
“yaml”
“pp”
=> nil
irb(main):005:0> p ‘yaml’, ‘pp’
“yaml”
“pp”
=> nil
“I don’t understand why this is considered cumbersome. Certainly it’s
more readable than looping over an array, and it’s not like this is
something you have to type a lot, or read a lot.”
Hi there,
It becomes cumbersome if you do like 20 lines of requires.
I can’t recall the last time I had more than eight requires in a
file. I think I can stretch back and recall five, but they’re in a
file I never touch anyhow (a top-level require everything file).
Putting them all on one line makes diffs hard to read.
The world isn’t going to run out of carriage returns or line feeds
any time soon.
I guess I should have phrased my question differently, seeing that it
spawned
side-questions including an even … rather … odd … notice that “the
world isn’t going to run out of carriage returns or line feeds any time
soon …”
Why does require allow only one argument?
We had that discussion a few weeks ago and as far as I remember the
outcome was: it’s the way it is and it’s not worth the effort to change
it.
Whops, that was a quick too fast. It seems to work with:
require ‘yaml’,‘pp’
but not with:
require %w( yaml pp )
TypeError: can’t convert Array into String
You need require *%w(…) with the redefinition that Jesse gave. Note
the asterix.
One reason why I do not so much like require ‘something’ is because of
the
‘’
Well, then you can do this - even without hacking the standard require:
%w{pathname fileutils English abbrev}.each {|r| require r}
Or, formatted differently
%w{
pathname
fileutils
English
abbrev
}.each {|r| require r}
IMHO changing “require” is not such a good idea as this change will be
overridden if you use gems for example. If you want multiple arguments,
then I’d rather define a new method
def r(*a) a.flatten.each {|f| require f} end
Then you can do
r %w{
pathname
fileutils
English
abbrev
}
r ‘pathname’,
‘fileutils’,
‘English’,
‘abbrev’
You can even replace the #each with #map to get all the return values.
