Scoping issue with quibble scribbles

[leios]

As noted here: #4 (comment)

There is a slight issue with the scoping logic for pointers using the same variable name for verses, stanzas, and poems. Here's an example script that shows the issue:

#include "stdio.h"
#include "stdlib.h"

int main(){
    int n = 0;
    int *c = calloc(1, sizeof(int));
    c[0] = 5;
    printf("C: %d\n", c[0]);

    {
        int *a = c;
        a[0] = 100;
        int n = 1;
        printf("%d\n", n);
    }
    printf("C: %d\n", c[0]);
    printf("%d\n", n);
    return 0;
}

Essentially, we need to define a new variable for pointers (in this case c -> a for internal blocks. Because we use thismethod for creating prologues for verses and stanzas, there is a possibility that users will use the same variabe (c in this case), which will cause a segfault when using c[0] (instead of a[0]) in the inner block.

The quick fix for now is simply to make sure that the variable names in all stanza, verse, and poem arguments are unique.

[leios]

As a note, we also cannot do things like:

@scall check(a = a;){}

Where the variable is the same as the value for kwargs.