search for: shallow_duplicate

...fails, raising the error back in do_subassign2_dflt(), because the assignment kind is invalid: there is no way to put data.frames into an expression vector. The new resized `x` is lost, and the old overwritten `x` stays there. Not sure what the right way to fix this is. It's desirable to avoid shallow_duplicate(x) for the overwriting assignments, but then the sub-assignment must either succeed or leave the operand untouched. Is there a way to perform the type check before overwriting the operand? -- Best regards, Ivan

...in > do_subassign2_dflt(), because the assignment kind is invalid: there is > no way to put data.frames into an expression vector. The new resized > `x` is lost, and the old overwritten `x` stays there. > > Not sure what the right way to fix this is. It's desirable to avoid > shallow_duplicate(x) for the overwriting assignments, but then the > sub-assignment must either succeed or leave the operand untouched. > Is there a way to perform the type check before overwriting the operand? Yes. There are two places where there are some checks, one early and the other late. The early one...

There seems to be a bug in out-of-bounds assignment of list objects to an expression() vector. Tested on release and devel. (Many thanks to folks over at Mastodon for the help narrowing down this bug) When assigning a list into an existing index, it correctly errors on incompatible type, and the expression vector is unchanged: ``` x <- expression(a,b,c) x[[3]] <- list() # Error x #>