HALT
HALT is a language designed for string processing which is currently under development.
Overview
HALT takes instructions, each prepended with a line number.
Comments
A line beginning with a # will make that line a comment. A line beginning with ---, denotes a second pass, taking the output as input.
Flow
HALT functions by keeping track of two main variables. HALT requires an input, it can even be a blank string. The pointer, and the instruction number.
Pointer
The pointer stores the index that the program is at in the input string. When the pointer reaches -1 or reaches past the string's end, the program is halted. If ht pointer never reaches these parameters, the program will trapped in an infinite-loop
Instruction
The instruction number is the current instruction being executed. The instruction number, is specified by the number preceding the line.
Functions
| Name | Arguments | Description |
|---|---|---|
| Pointer | ||
| INCREMENT | None | Increments the pointer by 1 |
| CONTINUE | number | Increments the pointer by n |
| SET | number | Sets pointer to the specific value |
| Flow | ||
| HALT | None | The HALT function stops the program (sets pointer to -1). The output is printed to STDOUT
|
| NEXT | None | Sets pointer to the specific value |
| GOTO | number | Goes to instruction number n |
| Output Stack | ||
| STORE | number | Pushes character in string at pointer offset by n, to the output stack |
| TYPE | string | Pushes string to output stack |
| KEEP | number | Pushes character in string at pointer to output stack in index n |
| Other | ||
| IF | string, number[, ELSE, number] | If the characters, from the pointer are string. Goto line n1. Optionally, if ELSE exists as a third argument. If the expression instead evaluates to false Goto line n2
|
| GET | int, number[, ELSE, number] | IF(char at index n1 in output stack, n2, ELSE, n3) |
Examples
Hello World
1 TYPE "Hello, World!"; HALT;
Reversing Input
1 KEEP 0; INCREMENT;
Escaping Quotes
1 IF '"' 2 ELSE 7; 2 STORE 0; INCREMENT; IF "\\" 3 ELSE 4; 3 INCREMENT; GOTO 2; 4 IF '"' 5 ELSE 6; 5 HALT; 6 GOTO 2; 7 IF "'" 9 ELSE 8; 8 INCREMENT; GOTO 1; 9 STORE 0; INCREMENT; IF "\\" 10 ELSE 11; 10 INCREMENT; GOTO 9; 11 IF "'" 6 ELSE 12; 12 GOTO 9;