Calling procedures with delayed substitutions

[tueda]

I was just trying some tricky things and found the following code makes FORM freeze:

#define CALL(a) "
#call Test(`~a')
"

#procedure Test(a)
  #message a=`a'
#endprocedure

`CALL(1)'

.end

It seems to be an interference of the variables with the same name "a" between calling the procedure and the delayed substitution.

A workaround can be (1) to use different names:

#define CALL(a1) "
#call Test(`~a1')
"

#procedure Test(a)
  #message a=`a'
#endprocedure

`CALL(1)'

.end

or (2) not to give the arguments for the procedure (although it is a bit mysterious why it works):

#define CALL(a) "
#call Test
"

#procedure Test
  #message a=`a'
#endprocedure

`CALL(1)'

.end