[Rd] value of a loop broken by break

[Peter Dalgaard]

Gabor Grothendieck <ggrothendieck at myway.com> writes:

> Should the 'for' loop in the following example not return 3 rather than 2?
> The Language Manual says that it returns the result of the last evaluated
> statement and that would be the i before the 'break'.  'repeat' and 'while'
> have the same behavior.
> 
> R> (for(i in 1:10) if (i==3) { i; break } else i)
> [1] 2

Hmmm... First, let's look at some variants:

>  (for(i in 1:10) {pi; if (i==3) { i; break } else 123})
[1] 123

Notice that you're getting neither "2" nor "3.1415926", but the "123"
from the previous iteration. Similarly

>  (for(i in 1:10) {pi; if (i==3) { i; break }else 123; 456})
[1] 456

So you are getting the result of the last _completely_ evaluated
statement (the enclosing "{"-statement is not completed either).

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
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