Welcome to jambda-calc

An npm package for transpiling JS/TS into λ calculus, and visualizing expressions with Tromp Diagrams.

Lambda calculus is one of the most simple Turing-complete languages, meaning that theoretically any valid programmatic function can be transpiled from it's native language, into a lambda expression.

In lambda calculus, everything is considered a function and creates the computation

Turing complete, simple language. Everything is a fn. Link to vid Vision is to process entire js projects into diagrams

Transpiler Functionality:

The transpiler (for converting JS/TS code into lambda calc), has handling for input files containing:

• Arithmetic (+, -, /, *)
• Common JS operators (!=, ==, ===)
• Number/boolean literals (-100 to 100, true/false)
• Conditionals (if else, switches)
• Nested functions (defined in the same input file)
• Basic member functions like .filter() and .map()

Not yet implemented:

• String operations
• Recursion
• Async functions
• let/var
• Increment/decrement (SUCC)
• Imported functions/modules from other files/dependencies
• Other member functions (Math.cos(), Math.log()) - Get abstracted as ((λobj.λprop.obj prop) ${func} (λx.x))

Visualizer Functionality

The visualizer converts formal λ calculus into Tromp Diagrams.

• Lambda abstractions (functions) are represented as horizontal lines across the top.
• Variables (params) cross abstraction lines vertically.
• Applications connect the bottom-left corners of terms being applied.

Installation

pnpm install jambda-calc

Note: Using pnpm for these examples, but npm works exactly the same.

CLI Usage

After installing in your project directory, you can use pnpm jambda-calc with various flags to run transpilation or visualization from the command line.

Helper Commands

pnpm jambda-calc examples - Run three example functions through transpilation and visualization.

pnpm jambda-calc --help - Display the options for flags.

Basic commands

• pnpm jambda-calc -i path/to/input-file.js: Runs transpilation and visualization on an input file (required). Prints results to console.
• pnpm jambda-calc -i path/to/input-file.js -t: Only run transpilation.
• pnpm jambda-calc -i path/to/lambda-expression.txt -v: Only run visualization (input file containing lambda expression to visualize).

Flags

• -i, --input: Input file to run transpilation or visualization on. (Required)
• -o, --output: Output dir to save output files: lambda expression (.txt) and/or tromp diagram (.png). Prints in console if not specified.
• -t, --transpile and -v, --visualize: Choose which task(s) to preform, if neither is specified, it runs both. If only visualize is set, it will expect a .txt input file containing an expression.
• -f, --format: Specify the file extension of the tromp diagram being saved: png or svg.