Feature #12318: Returning the evaluated value of a block

• Status: Closed
• Assignee: -
• Target version: -

[sawa (Tsuyoshi Sawada)]

I often achieve an element using an iterator with a block, and then apply the same/a similar block to the element I get. Examples are:

[7, 8, 9]
.max_by{|e| e % 3}
.tap{|e| break e % 3}
# => 2

["foo", "bar", "baz"]
.find{|e| e[/(.)\1/]}
.tap{|e| break e[/(.)\1/]}
# => "oo"

I would like a method on Enumerator that returns the result of the block rather than the original element in the iterator. Not sure about the name, but if I call it and_return temporary, it should look like:

[7, 8, 9]
.max_by.and_return{|e| e % 3}
# => 2

["foo", "bar", "baz"]
.find.and_return{|e| e[/(.)\1/]}
# => "oo"

[nobu (Nobuyoshi Nakada)]

It doesn't seem generic enough to be defined in Enumerator.
The receiver enumerator may return different object than its elements nor the results of the given block, whereas that and_return has to manage the association of them.

Why not simpler:

[7, 8, 9].map {|e| e % 3}.max
# => 2

["foo", "bar", "baz"].find {|e| break e if e = e[/(.)\1/]}
# => "oo"

or

["foo", "bar", "baz"].grep(/(.)\1/) {break $&}
# => "oo"

[avit (Andrew Vit)]

This is now implemented as yield_self

Close please?

[shyouhei (Shyouhei Urabe)]

• Status changed from Open to Closed

avit (Andrew Vit) wrote:

This is now implemented as yield_self

Close please?

Yes. Closing.