eval and tcltk : target of assignment expands to non-language object

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Hi everyone,

I have a problem to assign a value with tcl/tk
Not really. You'll get into the same sort of trouble if you try other kinds of complex assignments:
a <- 1:2
eval(as.name("a"))[[1]]
[1] 1
eval(as.name("a"))[[1]] <- 3
Error in eval(as.name("a"))[[1]] <- 3 : 
  target of assignment expands to non-language object

This is similar to Lumley's fortune("parse"): You may want to rethink the question. Wouldn't 

l <- list(A=tclVar("0"), B=tclVar("0"), B=tclVar("0"))
...
tclvalue(l[[id]]) <- ....

do the job much neater?

However if you insist, I suspect you need to use bquote() and an outer eval(), as in

eval(bquote(.(as.name("a"))[[1]] <- 3))
ths is the code ( it should be simple to understand) :

library(tcltk)

valA<-tclVar("0")
valB<-tclVar("0")
valC<-tclVar("0")
id<-"A"
out<-"1"
out2<-"2"

print(paste("tclvalue(val",id,")",sep="")) # ok
print(as.name(paste("tclvalue(val",id,")",sep=""))) #ok
print(eval(as.name(paste("val",id,sep="")))) #seems to be OK
print(tclvalue(eval(as.name(paste("val",id,sep=""))))) #ok
print("fin")

tclvalue(valA)<-out # this is good
tclvalue(valA)
tclvalue(paste("val",id,sep="")) #dont work but its normal
tclvalue(as.name(paste("val",id,sep="")))# dont work...
eval(as.name(paste("val",id,sep="")))# ok
tclvalue(eval(as.name(paste("val",id,sep=""))))#ok
is(eval(as.name(paste("val",id,sep=""))))

#that is what I want to do but it dont work :
tclvalue(eval(as.name(paste("val",id,sep=""))))<-out2
#>target of assignment expands to non-language object

# Have you any idea to do what I want to do?

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