FFLT lang

FFLT lang is essentially isomorphic to esoteric language Whitespace.
FFLT lang use F, L, T instead of SPACE, TAB, LF, and all other characters are ignored.
No case sensitivity except for label parameter.

Usage

fflt_lang program.fflt

Building yourself

make build

FFLT lang specification

Each command consists of a series of tokens, beginning with the Instruction Modification Parameter (IMP).
These are listed in the table below.

IMP	Meaning
F	Stack Manipulation
LF	Arithmeric
LL	Heap access
T	Flow Control
LT	I/O

Stack Manipulation (IMP:[F])

Command	Parameters	Meaning
F	Number	Push the number onto the stack
LF	Number	Copy the nth item on the stack (given by the argument) onto the top of the stack
LT	Number	Slide n items off the stack, keeping the top item
TF	-	Duplicate the top item on the stack
TL	-	Swap the top twe item on the stack
TT	-	Discard the top item on the stack

Arithmetic (IMP:[LF])

Command	Parameters	Meaning
FF	-	Addition
FL	-	Subtraction
FT	-	Multiplication
LF	-	Integer Division
LL	-	Modulo

Heap Access (IMP:[LL])

Command	Parameters	Meaning
F	-	Store
L	-	Retrieve

Flow Control (IMP:[T])

Command	Parameters	Meaning
FF	Label	Mark a location in the program
FL	Label	Call a subroutine
FT	Label	Jump unconditionally to a label
LF	Label	Jump to a label if the top of stack is zero
LL	Label	Jump to a label if the top of stack is negative
LT	-	End a subroutine and transfer control back to the call
TT	-	End the program

I/O (IMP:[LT])

Command	Parameters	Meaning
FF	-	Output the character at the top of the stack
FL	-	Output the number at the top of the stack
LF	-	Read a character and place it in the location given by the top of the stack
LL	-	Read a number and place it in the location given by the top of the stack

Number and Label

Number

	Sign	Bits F = 0, L = 1	Terminated by a T
Example	F	LF	T	= 2

Label

Label is case sensitive

	Label	Terminated by a T
Example	FL	T

Example

FFFLFT	Push 1 onto the stack
TFFLT	Set a label "L" at this position
TFLLT	Jump to label "L"