Solution to the problem of pre-assigned variables to 0

[compsystems]

Hello, in the first code using quotation marks the expression is not evaluated, that is to say it is kept symbolic.

PHP Code:

#cas
prg01(  ):=
    begin
        PRINT; 
        print(   'X²/3 - Y²/5 = 1'  );  // ' Do not evaluate
        print(   X²/3 - Y²/5 = 1  );  //  X -> 0
        return 'X²/3 - Y²/5 = 1' ;
    end;
#end 


prg01( ) [enter]
show
X²/3 - Y²/5 = 1
0=1


in the second code, assume X as symbolic, there is no need to use ' '
this same procedure should work assuming X as noValue

PHP Code:

#cas
    prg02(  ):=
    begin
        local X, Y; 
        assume(X, symbol); //  assume X as symbolic
        assume(Y, symbol); 
        print( X²/3 - Y²/5 = 1 );
        return  X²/3 - Y²/5 = 1;
    end;
#end 


prg02( ) [enter]
show
X²/3 - Y²/5 = 1