Dear R-devel,
I found this behavior disturbing, if `1 + f()` is called, `sys.call()`
called inside of `f` will return a quoted `f()` with a "srcref" that
prints
"1 + f()".
I don't know which one is good but I don't think they can be correct at
the
same time.
Here's a reproducible example:
f <- function(){
sc <- sys.call()
print(sc)
attr(sc, "srcref") <- NULL
print(sc)
1
}
f2 <- function() {
1 + f()
}
f()
#> f()
#> f()
#> [1] 1
f2()
#> 1 + f()
#> f()
#> [1] 2
Best,
Antoine
[[alternative HTML version deleted]]
Hello, The source references are useful for debugging tools because they allow linking to call sites in the source files. I agree the output can be confusing. Perhaps this could be fixed by tweaking the print method for calls. If the deparsed call doesn't match the srcref, both could be displayed along with file:line:column. ``` #> f() #> <srcref:file.R:2:3> #> 1 + f() ``` Best, Lionel On 9/2/20, Antoine Fabri <antoine.fabri at gmail.com> wrote:> Dear R-devel, > > I found this behavior disturbing, if `1 + f()` is called, `sys.call()` > called inside of `f` will return a quoted `f()` with a "srcref" that prints > "1 + f()". > > I don't know which one is good but I don't think they can be correct at the > same time. > > Here's a reproducible example: > > f <- function(){ > sc <- sys.call() > print(sc) > attr(sc, "srcref") <- NULL > print(sc) > 1 > } > f2 <- function() { > 1 + f() > } > f() > #> f() > #> f() > #> [1] 1 > f2() > #> 1 + f() > #> f() > #> [1] 2 > > Best, > > Antoine > > [[alternative HTML version deleted]] > > ______________________________________________ > R-devel at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel >
Thanks Lionel, I now understand what's going on. I like your proposal and I can confirm I wouldn't have been confused had it be printed this way. In fact I wouldn't mind the file:line:column to be displayed every time. Best, Antoine Le jeu. 3 sept. 2020 ? 00:19, Lionel Henry <lionel at rstudio.com> a ?crit :> Hello, > > The source references are useful for debugging tools because they > allow linking to call sites in the source files. > > I agree the output can be confusing. Perhaps this could be fixed by > tweaking the print method for calls. If the deparsed call doesn't > match the srcref, both could be displayed along with file:line:column. > > ``` > #> f() > #> <srcref:file.R:2:3> > #> 1 + f() > ``` > > Best, > Lionel > > > On 9/2/20, Antoine Fabri <antoine.fabri at gmail.com> wrote: > > Dear R-devel, > > > > I found this behavior disturbing, if `1 + f()` is called, `sys.call()` > > called inside of `f` will return a quoted `f()` with a "srcref" that > prints > > "1 + f()". > > > > I don't know which one is good but I don't think they can be correct at > the > > same time. > > > > Here's a reproducible example: > > > > f <- function(){ > > sc <- sys.call() > > print(sc) > > attr(sc, "srcref") <- NULL > > print(sc) > > 1 > > } > > f2 <- function() { > > 1 + f() > > } > > f() > > #> f() > > #> f() > > #> [1] 1 > > f2() > > #> 1 + f() > > #> f() > > #> [1] 2 > > > > Best, > > > > Antoine > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-devel at r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-devel > > >[[alternative HTML version deleted]]
>On Wednesday, September 2, 2020, 6:19:20 PM EDT, Lionel Henry <lionel at rstudio.com> wrote: > >Hello, > >The source references are useful for debugging tools because they >allow linking to call sites in the source files. > >I agree the output can be confusing. Perhaps this could be fixed by >tweaking the print method for calls. If the deparsed call doesn't >match the srcref, both could be displayed along with file:line:column. > >``` >#> f() >#> <srcref:file.R:2:3> >#> 1 + f() >``` > >Best, >LionelWhy print the mismatched srcref at all?? I find that confusing. Just omit the srcref from display. Debugging tools can still retrieve it and use the information, presumably. Best, Brodie.