Weird issue when iterating through dates

I am not sure if this is a bug or not.

I would argue that this isn't a bug, not even in the documentation of
"for" (even though it might be clearer).  ?"for" says that `seq` is
"[A]n expression evaluating to a vector (including a list and an
expression) or to a pairlist or 'NULL'".  Date objects aren't strictly
vectors, so they're treated as integer/numeric.

This answer on StackOverflow said that "for" does not copy any of the
iterators attributes (including class), which causes this behavior.
http://stackoverflow.com/a/23278464/271616

To respond to the original question regarding why the code below,
"prints the dates as a string".  Quite simply, you convert seq(d1,d2,
by=1) to character, so it's no longer a Date.  The fact that
Sys.Date() and as.character(Sys.Date()) both *print* the same thing
does not mean they are the same.

for ( dt in as.character(seq(d1,d2, by=1)) ) {
  print(dt)
}

Best,
Josh
Gabor

On Wed, Aug 12, 2015 at 11:51 AM, Luca Cerone <luca.cerone at gmail.com> wrote:
Following up on this, should I report a bug? can you drive me through
the process?

Cheers,
Luca

On Thu, Aug 6, 2015 at 4:55 PM, William Dunlap <wdunlap at tibco.com> wrote:
Just a quick question: what's the difference between  `[.Date` and
`[[.Date`?
Is it supposed to be the method for accessing the value right?
For Dates and atomic vectors in general they are the same, but ...
Even for atomic vectors with names they are not quite the same
    > c(One=1, Two=2)[[2]]
    [1] 2
    > c(One=1, Two=2)[2]
    Two
      2
(and [[ will only return 1 item, unlike [).

Bill Dunlap
TIBCO Software
wdunlap tibco.com

On Thu, Aug 6, 2015 at 5:36 AM, G?bor Cs?rdi <csardi.gabor at gmail.com> wrote:
On Thu, Aug 6, 2015 at 6:30 AM, Luca Cerone <luca.cerone at gmail.com> wrote:
[...]
Just a quick question: what's the difference between  `[.Date` and
`[[.Date`?
Is it supposed to be the method for accessing the value right?
For Dates and atomic vectors in general they are the same, but in
general they are two different operators that behave differently on
some data types. E.g. on lists [ selects a sub-list and [[ selects a
single element.

Gabor

[...]

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Weird issue when iterating through dates

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