[R] substitute() reading data instead of name

[Peter Dalgaard]

Steven McKinney wrote:
>
> You can either put code such as these first two lines
> to grab the names of x and y before you alter x and y
> in your function
>
>
> badplot <- 
> function(x, y, ylab, xlab,  ...)
> {
> if (missing(ylab)) ylab <- deparse(substitute(y))
> if (missing(xlab)) xlab <- deparse(substitute(x))
>
>   
....
> or use another mechanism such as match.call()
>
>
> anotherbadplot <- 
> function(x, y, ylab=match.call()$y,
> xlab=match.call()$x,  ...)
> {
>   
....

> but I don't see any bug here.
>   
A more direct fix is to put

force(ylab)

somewhere early in the function, before modifying y.

-- 
   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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