James Eversole
c9d0d04630
To encourage organizing code in a way that helps in understanding, I have implemented the common idiom of requiring a `main` function. In tricu and other functional languages, it is usually placed near the top of the module. The evaluator gracefully handles the situation of passing multiple files where the intermediary "library" files do not have main functions.
tricu
Introduction
tricu (pronounced "tree-shoe") is a purely functional interpreted language implemented in Haskell. It is fundamentally based on the application of Tree Calculus terms, but minimal syntax sugar is included to provide a useful programming tool. tricu is under active development and you can expect breaking changes with nearly every commit.
tricu is the word for "tree" in Lojban: (x1) is a tree of species/cultivar (x2).
Features
- Tree Calculus operator:
t - Assignments:
x = t t - Lambda abstraction syntax:
id = (\a : a) - List, Number, and String literals:
[(2) ("Hello")] - Function application:
not (not false) - Higher order/first-class functions:
map (\a : lconcat a "!") [("Hello")] - Intensionality blurs the distinction between functions and data (see REPL examples)
- Immutability
REPL examples
tricu < -- Anything after `--` on a single line is a comment
tricu < id = (\a : a) -- Lambda abstraction is eliminated to tree calculus terms
tricu < head (map (\i : lconcat i " world!") [("Hello, ")])
tricu > "Hello, world!"
tricu < id (head (map (\i : lconcat i " world!") [("Hello, ")]))
tricu > "Hello, world!"
tricu < -- Intensionality! We can inspect the structure of a function or data.
tricu < triage = (\a b c : t (t a b) c)
tricu < test = triage "Leaf" (\z : "Stem") (\a b : "Fork")
tricu < test (t t)
tricu > "Stem"
tricu < -- We can even convert a term back to source code (/demos/toSource.tri)
tricu < toSource not?
tricu > "(t (t (t t) (t t t)) (t t (t t t)))"
tricu < -- or calculate its size (/demos/size.tri)
tricu < size not?
tricu > 12
Installation and Use
Releases are available for Linux.
Or you can easily build and/or run this project using Nix.
- Quick Start (REPL):
nix run git+https://git.eversole.co/James/tricu
- Build executable in
./result/bin:nix build git+https://git.eversole.co/James/tricu
./result/bin/tricu --help
tricu Evaluator and REPL
tricu [COMMAND] ... [OPTIONS]
tricu: Exploring Tree Calculus
Common flags:
-? --help Display help message
-V --version Print version information
tricu [repl] [OPTIONS]
Start interactive REPL
tricu eval [OPTIONS]
Evaluate tricu and return the result of the final expression.
-f --file=FILE Input file path(s) for evaluation.
Defaults to stdin.
-t --form=FORM Optional output form: (tree|fsl|ast|ternary|ascii|decode).
Defaults to tricu-compatible `t` tree form.
tricu decode [OPTIONS]
Decode a Tree Calculus value into a string representation.
-f --file=FILE Optional input file path to attempt decoding.
Defaults to stdin.
Acknowledgements
Tree Calculus was discovered by Barry Jay.
treecalcul.us is an excellent website with an intuitive Tree Calculus code playground created by Johannes Bader that introduced me to Tree Calculus.