TITLE: The First Rule of Programming in Ruby
AUTHOR: Eugene Wallingford
DATE: June 13, 2012 2:19 PM
DESC:
-----
BODY:
When I was thinking about implementing the cool programming
idiom I
blogged about yesterday,
I forgot the first rule of programming in Ruby:
It's already in there.
It didn't take long after my post went live that readers began
to point out that Ruby already offers the functionality of my
sub and R's { operator, via
Array#values_at:
>> [10, 5, 9, 6, 20, 17, 1].values_at(6, 1, 3, 2, 0, 5, 4)
=;> [1, 5, 6, 9, 10, 17, 20]
I'm not surprised. I should probably spend a few minutes every
day browsing the documentation for a randomly-chosen Ruby class.
There's so much to find! There's also too much to remember out
of context, but I never know when I'll come across a need and
have a vague recollection that Ruby already does what I need.
Reader Gary Wright pointed out that I can get closer to R's
syntax by aliasing values_at with an unused
array operator, say:
class Array
def %(*args)
values_at(*args.first)
end
end
Now my use of % is as idiomatic in Ruby as
{ is in R:
>> [10, 5, 9, 6, 20, 17, 1] % [6, 1, 3, 2, 0, 5, 4]
=;> [1, 5, 6, 9, 10, 17, 20]
I am happy to learn that Ruby already has my method and am just
as happy to have spent time thinking about and implementing it
on my own. I like to play with the ideas as much as I like
knowing the vast class library of a modern scripting language.
(If I were writing Ruby code for a living, my boss might not
look upon my sense of exploration so favorably... There are
advantages to being an academic!)
-----