Shrimp Language

Overview

Shrimp is a shell-like scripting language that combines the simplicity of command-line interfaces with functional programming concepts. Built using Lezer (CodeMirror's parser system) with TypeScript.

Language Design Philosophy

• Everything is an expression - Commands, assignments, and functions all return values
• Whitespace matters - Spaces distinguish operators from identifiers (e.g., x-1 is an identifier, x - 1 is subtraction)
• Shell-like command syntax - echo hello world works naturally
• Named arguments without quotes - tail file.txt lines=30
• Unbound symbols become strings - echo hello treats hello as a string if not defined
• Simplicity over cleverness - Each feature should work one way, consistently. Two simple features that are easy to explain beat one complex feature that requires lots of explanation

Current Status & Goals

Today's Implementation Goals

1. ✅ Interpreter Setup - Renamed evaluator to interpreter for clarity
2. Command Execution - Support calling external commands and built-in functions
3. Variable Assignment - Implement assignment with validation using Lezer context tracking

Parser Features

• ✅ Distinguishes between identifiers (assignable) and words (non-assignable)
• ✅ Smart tokenization for named args (lines=30 splits, but ./path=value stays together)
• ✅ Handles ambiguous cases (bare identifier could be function call or variable reference)

Grammar Architecture

See src/parser/example.shrimp for language examples and src/parser/shrimp.grammar for the full grammar.

Key Token Types

• Identifier - Lowercase/emoji start, can contain dashes/numbers (assignable)
• Word - Any non-whitespace that isn't a valid identifier (paths, URLs, etc.)
• FunctionCall - Identifier followed by arguments
• FunctionCallOrIdentifier - Ambiguous case resolved at runtime