T

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What is...it?

It's a esolang with painfully vertical data storage. You only get 3 registers to work with, though you can compress the registers into archives, but an archive takes a register, and it's difficult to avoid overwriting your own data when extracting them.

It's still a work-in-progress while I figure out whether it's powerful enough to solve complex problems. I think it's almost done, though.

Yes, the name is written vertically like that. I'm avoiding writing it as much as I can.

Syntax

Data Types

There are two data types: numbers and archives. Numbers can also be treated as UTF-8 characters in certain statements and expressions. Numbers are stored as 32-bit signed integers. Nonzero numbers are truthy, and zero is falsy.

Archives have up to three registers of their own, each of which may contain a number or another archive. All archives are truthy.

Statements

Any character tries to be a statement by default. A symbol only becomes an expression if a previous statement or expression coerces it into one. Later characters have coercion priority over earlier ones. For example (you may want to reference the tables below for this example), in ?&bc#a[, ? coerces & into an expression, which coerces b and c into expressions. # is the next available character, so ? coerces it into a statement, and # coerces a into an expression. ?&bc#a is a complete statement, so [ becomes a statement by default.

Statement	Description	Example	Example notes
. <Expr>	Print the expression as a number	.:1	Prints 1
, <Expr>	Print the expression as a character	,;A	Prints A
a <Expr>, b <Expr>, c <Expr>	Store the expression in register a, b, or c	a:1	Stores 1 in register a
? <Expr> <Stmt>	Execute the statement if the expression is truthy	?:0.:1	Prints nothing
[	Jump forward, just after the matching ]	?:1[.:1].:0	Skips 1 and prints 0
]	Jump back, just after the matching [	?:0[.:1].:0	Prints 1 forever
# <Expr>	Extracts the expression, if it's an archive. Registers are overwritten with the registers stored in the archive. Registers that do not have a value in the archive are not overwritten.	#a	Extracts the archive a

Expressions

Expression	Description	Example	Example notes
: <Number>	A number literal	.:-1	Prints -1
; <Character>	A character literal	.;A	Prints 65
.	Read a number from the buffer. If the buffer is empty, it is refilled from stdin.	a.	Stores a number from stdin to register a
,	Read the next character from the buffer. If the buffer is empty, it is refilled from stdin. The buffer will always end with \r, then \n.	,,	Echos a character from the buffer to stdout
a, b, c	Gets the value of register a, b, or c	.a	Prints the value of register a as a number
+ <Expr> <Expr>	Add two numbers	.+:1:2	Prints 3
- <Expr> <Expr>	Subtract two numbers	.-:1:2	Prints -1
* <Expr> <Expr>	Multiply two numbers	.*:4:3	Prints 12
/ <Expr> <Expr>	Divide two numbers	./:12:5	Prints 2
% <Expr> <Expr>	Modulo two numbers	.%:12:5	Prints 2
! <Expr>	Logical NOT. Evaluates to 1 for any falsey value, and 0 for any truthy value. All archives are truthy.	.!:-1	Prints 0
& <Expr> <Expr>	Logical AND	.&:1a	Prints 1 if register a is truthy, and 0 otherwise
| <Expr>	Logical OR	.|:0a	Prints 1 if register a is truthy, and 0 otherwise
= <Expr> <Expr>	Checks whether the expressions equal. Any archive is considered equal to any other archive.	.=:-1-:3:2	Prints 1
< <Expr> <Expr>	Checks whether the first expression is less than the second	.<:3:5	Prints 1
> <Expr> <Expr>	Checks whether the first expression is greater than the second	.>:3:5	Prints 0
? <Expr> <Expr> <Expr>	Conditional. If the first expression is truthy, it resolves to the second expression. Otherwise, it resolves to the third expression.	,?;A;B;C	Prints C
[ <Registers> ]	Creates an archive of the given registers	c[ac]	Creates an archive containing the current values of registers a and c, and stores it in register c

+, -, *, /, %, >, and < evaluate to 0 if either expression is an archive

Examples

You can find the examples in the examples directory. I recommend trying to solve some of these problems yourself first, and looking at examples if you need help. If following examples are roughly ordered by difficulty.

Example	Description
hello_world.twr	Prints Hello, world!
fibonacci.twr	Prints Fibonacci numbers until it crashes from overflow
primes.twr	Prints prime numbers
factorial.twr	Calculates the factorial of a given number
99_bottles.twr	Prints the lyrics to "99 Bottles of Beer". Reuses as much of the text as is practical.
echo.twr	Echos the given input to output
bracket_checker.twr	Checks whether given brackets are balanced
sort.twr	This is an unfinished implementation of a sorting algorithm. Once this example is completed, and necessary modifications are made to the language, I plan to release its 1.0.

Installation

Install Rust and clone the repo.

Usage

Run a .twr file with tower <file>. If running through cargo (which you should), it will look like cargo run <file>.

Contributing

If you have a suggestion, bug report, or contribution, feel free to open an issue or pr.

License

T
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is dual-licensed under either

• MIT License (LICENSE-MIT or http://opensource.org/licenses/MIT)
• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)

at your option.