Textile

Textile (not to be confused with the markup language under the same name) is an attempt at a textual form of Tile created by User:Dtp09. Its name is a portmanteau of the words "Text" and "Tile", which is basically what it is.

Textile was created to allow for somewhat readable Tile programs, as well as functioning as a somewhat easier way to write complex Tile programs without worrying about how to route the PC across the grid.

Comments

Comments are indicated by a hashtag (#) and comment out the rest of the line. Block comments do not exist

Functions

Functions (not to be confused with the top level language definition of a function) are blocks of code that the PC can execute during runtime. Functions are not subroutines and do not return to where they were called from after execution. A function can be jumped to from anywhere in the program, both before and after it is declared. Functions can be declared with any alphanumeric label as follows:

LABEL: {
#code goes here
}

Starting a program

All textile programs are required to have a function either called "main" or "MAIN". This is where the PC will start. If the program contains both functions MAIN and main, or neither, then the program will not run. If there is a debug command in the main function, that is where the PC will start.

Opcodes

Opcodes are case insensitive. They can be written in uppercase or lowercase or even a mix of both. "NOP" and "Empty" tile states have been removed entirely, as they don't have any function outside of routing the PC across the grid. Every instruction has both a three digit opcode and a full length opcode, either of which can be written and will execute the same instruction.

Tile	Opcode
▀░	psh / push
░▀	red / read
▀▀	out / output
▄░	sub / subtract
█░	add
▄▀	mul / multiply
█▀	div / divide
░▄	wrt / write
▀▄	ran / random
░█	inp / input
▀█	equ / equal
▄▄	jmp / jump
█▄	les / less
▄█	gtr / greater
██	dbg / debug

Command Repitition

Commands can be repeated multiple times in a row with the same operands. They are represented by an asterisk followed by the repetition count. For example, "push*2 $FF" would push 255 to the stack twice.

Operands

Operands come after an opcode and are seperated by commas. Opcodes such as push, jump, greater, less, equal, and random all have operands,

Push

Push is a very unique opcode. there are many ways to push the same exact thing to make it easier to read. You can push both numbers and ASCII strings to the stack. Push can have no opcodes (same as push 0) or as many as you want (push many values to the stack).

Number

Numbers come in 8-bit unsigned integers. They can come in binary (prefixed %), decimal (no prefix), or hex(prefixed $). For example, to push decimal 108 you can do any of the following:

• push $6C
• push 108
• push %01101100

Strings

Pushing a string will push the ASCII code of each character to the stack, ending with the top stack value being the last character in the string. They are represented by text encased in quotes or double-quotes. For example:

push "Tile"

This would push (from bottom to top) 84, 105, 108, 101. In a typical output loop this would output in reverse due to how the stack works.

String constants only have one method, and that is String.reverse, which will push every character to the stack in reverse order

Greater, Less, Equal, Jump, Random

These all have one thing in common and that is they all use functions as opcodes. greater, less, equal, and jump have 1 parameter each, while rand can take 1, 2, or 3. They operate similarly to how they do in Tile, with the "path to the right" being the function given for the comparison instructions, and the "path to the left" being anything after the comparison in the same function.

rand label1 label2 #jump to either function

Replacements

Replacements are special commands that "pastes" code from a function in the middle of another function. Replacements should be utilized when the same code is reused in a bunch of functions in a program. It's similar to calling a function with no parameters in a high level programming language. You can only use replacements with a function declared before the replacement, and not after. Any function can be used for a replacement.

LABEL: {
#code goes here
}
[LABEL] #the same code will be "pasted" here

Replacements also follow command repitition, such as for [LABEL]*2, where the function will be "pasted" into the program twice in a row.

Program termination

Programs can be terminated during a divide by zero, or if PC reaches the end of a function.

Examples

Hello, World!

MAIN: { 
push "Hello, World".reverse
jump OUTPUT
}

OUTPUT: {
out
push
equal EXIT
add
jump OUTPUT
}

EXIT: {
}

Cat Program

MAIN: {
input
push
equal EXIT #exit if it's a null byte
add
out #output our input
push 1
add #add to input read address
push
equal OVERFLOW #if the lower byte read address overflowed
add
jump MAIN
}

OVERFLOW: {
push 1
add*3 #add 1 to input read higher byte
push
jump MAIN
}

EXIT: {
}

Brainfuck

Written by User:Dtp09, the interpreter has unlimited loop depth, 8-bit unsigned cell storage, and 2^16-6 (65530) cells with wraparound. The program and the brainfuck input can be seperated by a semicolon. Since the program is about 500 lines, it is at Textile/brainfuck.

Compiler/Interpreter

A compiler and interpreter was written also by User:Dtp09 and is hosted here.