t4.txt

** Test case 4: Testing symbol table creation for variable declaration and redeclaration checks**
** Multiple level nesting using static array data type**
**Variant of test case 2**

<<module var_demo_array>>
takes input [x:integer, m:array [2..20] of integer, p:real];
returns [ n:integer, k: boolean];
start
	declare a,b:integer;	
	get_value(b);
	declare p: array[2..20] of integer;	**Not an error as local variable can shadow the definition of input parameter**
	a:= m[5]+3;
	p:= m;					** not an error**
	k:=true;
	p[10]:= a*b-20*h;			**ERROR: variable h is not declared**
	while(k AND x<=m[11] OR false)
	start
		declare p:integer;
		declare b: array[2..20] of integer;
		b:= m;
		b[2]:= u+m[6];			**ERROR: variable u is not declared**
		p:= b[18]*18;
	end							**  None of while loop variable is assigned  **
        n:= a - b;
	declare b:real;				**ERROR: variable b is re-declared**
	b:= b+3;
	k:= a>b OR b>100;
	print(k);	
end


<<module f1>>
takes input[a: array[10..30] of integer, b:array[10..30] of integer, c:real];
returns [m:boolean, n:integer];
start
	declare x,y: real;
	declare k: integer;
	get_value(y);
	get_value(x);
	declare A,B: array[4..10] of integer;
	get_value(B);
	declare C: array[10..30] of integer;
	A:=B;
	C:=a;
	D:=C;					**ERROR: variable D is not declared**
	for (k in -15..40)
	start
		x:=x+y;
		declare u, v:real;
		u := y+c*34.2;
		v:= u-c*p-20.5E+2;		**ERROR: variable p is not declared**
		switch(k)
		start
			case 10: declare A:real;
				 declare B: array[10..30] of integer;
				 declare E: array[4..10] of integer;
				 B[15]:= k*20; 	**No error as index is within bounds computed statically**	
				 B:=C;          **No error as C is available with static ancestor**
				 E:= Q;		**ERROR: variable Q is not declared**
				 break;
			case 20: declare B, A: array[-11..10] of real;     **Not an error: variables A, B are declared in the scope of this different case**
                                 A[3]:= 12.90 + u*y - c;         **Not an error as u, y and c are avialble in the scopes of static ancestors**
				 declare B: real;             **ERROR: variable B is re-declared**
				 declare Q: integer;
				 get_value(Q);
				 u:= k+12 - Q*10;      ** TYPE MISMATCH ERROR **    **not an error**
				 break;
			default: C[9]:= A[15]+Q;	 ** ARRAY ELEMENT A[15] IS OUT OF BOUND , VARIABLE Q NOT DECLARED **   ** C[9] is out of bound **
				 break;			 	
		end
		x:=x+u*v;
		k:= 23;				**ERROR: variable k is assigned a value erroniously as it is the variable in for loop**
	end
	x:=c+y;	
	C[18]:= a[18]+ b[18];
	A[5]:= B[6]- 10;
	declare A: array[10..70] of integer;	**ERROR: variable A is re-declared**
	m:= A[5]< C[18];
	m:= c>=x AND E[10]>=y;			**ERROR: variable E is not declared**
	n:= 20*8-5;	
end



<<<driver program>>>
start
	declare v_1_2_3, A:integer;
	declare u1:boolean;
        A:=12;
	declare p: real;
	p:= 23.56;
	get_value(v_1_2_43);							**ERROR: variable v_1_2_43 is not declared**		
	declare B, C: array [2..20] of integer;
	[ v_1_2_3, u1]:=use module var_demo_array with parameters A,B,p;		
	[ v_1_2_3, k]:=use module var_demo_array with parameters A,B,p;		**ERROR: variable k is not declared**
	B:= C;
	declare B: real;							**ERROR: variable B is re-declared**
end