rustack Wasm

Data types

rustack has following value types. It is dynamically typed language, so each stack element can have any type at any time.

• Int (i32)
• Num (f32)
• Symbol
• Block
• Native

Built-in functions

As an experimental language, it has only few Built-in functions.

• "puts" - Pop a value from the stack and print it to the console.
• "+" - addition
• "-" - subtraction
• "*" - multiplication
• "/" - division
• "<" - less-than (yields 1 if true, otherwise 0)
• "and" - logical AND (yields 1 if both of 2 operands are nonzero, otherwise 0)
• "or" - logical OR (yields 1 if both of 2 operands are nonzero, otherwise 0)
• "if" - conditional branching, taking 3 argument blocks
• "for" - Pop (start, end, block), loop from start through end, calling block with the iteration number pushed to the operand stack
• "def" - pop a symbol (name) and a value and define a variable (a scalar) or a function (a block)
• "pop" - pop the topmost value from the stack
• "dup" - duplicate the topmost value of the stack and push it
• "exch" - exchange the topmost 2 values
• "index" - pop a value from the stack, and extract a value at stack index specified by the popped value
• "load" - pop a value from the stack, get a value from dictionary stack with the popped value as the key and push it without executing it

Canvas rendering functions

• "rectangle" - Pop (x, y, width, height) values from the stack and render a filled rectangle in the canvas.
• "set_fill_style" - Pop (r, g, b) values from the stack and sets the color of following fill commands.
• "set_stroke_style" - Pop (r, g, b) values from the stack and sets the color of following stroke commands.
• "move_to" - Pop (x, y) values from the stack and call CanvasRenderingContext2D.moveTo
• "line_to" - Pop (x, y) values from the stack and call CanvasRenderingContext2D.lineTo
• "stroke" - Call CanvasRenderingContext2D.stroke
• "rotate" - Pop angle value from the stack and call CanvasRenderingContext2D.rotate
• "translate" - Pop (x, y) values from the stack and call CanvasRenderingContext2D.translate
• "save" - Call CanvasRenderingContext2D.save
• "restore" - Call CanvasRenderingContext2D.restore

Time measurement resolution

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