S42 - Stack based VM

It includes the standard operator of a generic stack based VM. It accept a one liner program, composed by

the stack is LIFO

• INT or FLOAT : put the value into stack
• ADD : to perform addition of the latest two values inserted
• SUB : to perform subtraction
• MUL : to perform multiplication
• DIV : to perform division
• DUP : to duplicate the latest value on the stack
• POP : to remove the latest inserted value on the stack
• < : to perform a comparison between the latest two values on the stack it put on the stack the boolean result.
• [x,y] : it perform an IF using the boolean result from a comparison returning on the stack x if true, y if false.
• {z} : put on the stack the program Z in order to be executed later, i.e.: {DUP,MUL}, with the command EXE.
• . : print out on the screen the latest value in the stack

Example

5 4 7 4 ADD . SUB MUL . 10 < [20,30] . {DUP,MUL} EXE .