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DelayedArray subsetting via lapply doesn't work

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
r
Domain
data

Research direction

Start by running the provided R reproduction with DelayedArray 0.19.4 and compare ordinary matrix subsetting with lapply on a DelayedArray. Trace the subsetting entry point and the sys.call() handling mentioned in the report; done means the lapply call returns the requested 5-by-2 subset without the '...' context error.

Written by the indexing model from the issue text.

Description

On DelayedArray 0.19.4:

x <- list(matrix(runif(100), 10, 10))
lapply(x, "[", i=1:5, j=1:2, drop=FALSE)
## [[1]]
##           [,1]       [,2]
## [1,] 0.5664114 0.89343894
## [2,] 0.9693973 0.07918907
## [3,] 0.1310845 0.20746916
## [4,] 0.6174420 0.48100379
## [5,] 0.5324374 0.82014878

library(DelayedArray)
y <- list(DelayedArray(x[[1]]))
lapply(y, "[", i=1:5, j=1:2, drop=FALSE)
## Error in eval(subscript, envir = eframe, enclos = eframe) : 
##   '...' used in an incorrect context

Not 100% sure what's happening here, just that there's some voodoo stuff going on with sys.call().

Dominant language
R
Stars
29
Forks
12
PR merge metrics
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