Result of 'seq' doesn't use compact internal representation

Thanks -- I'll commit a fix after some testing.

Best,

luke

On 04/29/2018 06:22 AM, Duncan Murdoch wrote:

On 28/04/2018 11:11 PM, Suharto Anggono Suharto Anggono via R-devel wrote:

.Internal(inspect(1:10))

@300e4e8 13 INTSXP g0c0 [NAM(3)]? 1 : 10 (compact)

.Internal(inspect(seq(1,10)))

@3b6e1f8 13 INTSXP g0c4 [] (len=10, tl=0) 1,2,3,4,5,...

system.time(1:1e7)

??? user? system elapsed
?????? 0?????? 0?????? 0

system.time(seq(1,1e7))

??? user? system elapsed
??? 0.05??? 0.00??? 0.04

It seems that result of function 'seq' doesn't use compact internal 
representation. However, looking at the code of function 'seq.default', 
seq(1,n) produces 1:n. What is going on?

It looks like it is related to using compiled or interpreted code:

 > library(gtools)
 > seq2 <- unByteCode(seq.default)
 > .Internal(inspect(seq.default(1,10)))

@7fa53847dcd8 13 INTSXP g0c4 [] (len=10, tl=0) 1,2,3,4,5,...

 > .Internal(inspect(seq2(1,10)))

@7fa537fa0bf0 13 INTSXP g0c0 [NAM(3)]? 1 : 10 (compact)

Duncan Murdoch

h <- seq.default
environment(h) <- .GlobalEnv
library(compiler)
enableJIT(0)

[1] 3

.Internal(inspect(h(1,10)))

@375ade8 13 INTSXP g0c0 [NAM(3)]? 1 : 10 (compact)

A non-byte-compiled version of function 'seq.default' can produce object 
that uses compact internal representation.

sessionInfo()

R version 3.5.0 (2018-04-23)
Platform: i386-w64-mingw32/i386 (32-bit)
Running under: Windows XP (build 2600) Service Pack 3

Matrix products: default

locale:
[1] LC_COLLATE=English_United States.1252
[2] LC_CTYPE=English_United States.1252
[3] LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C
[5] LC_TIME=English_United States.1252

attached base packages:
[1] compiler? stats???? graphics? grDevices utils???? datasets? methods
[8] base