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Interpreter

Language: Español | English

The Crespi interpreter (crespi) runs your code directly without compilation. It's ideal for development, learning, and scripting.

Quick Start

# Run a file
crespi program.crespi

# Run code directly
crespi -c 'print("Hello, World!")'

# Start interactive REPL
crespi

Execution Modes

Run File

crespi my_program.crespi

Executes the file and displays output in the terminal.

Type Check (Optional)

crespi --check my_program.crespi

Runs the static type checker before execution and exits on errors.

Inline Code

crespi -c 'var x = 5; print(x * 2)'

Useful for quick tests without creating files.

Interactive REPL

crespi
# or explicitly:
crespi repl

The REPL (Read-Eval-Print Loop) lets you write and execute code line by line:

Crespi REPL v0.0.1
Type 'exit' to exit

>>> var name = "Ana"
>>> print("Hello, " + name)
Hello, Ana
>>> exit

Debugging Commands

View Tokens

crespi tokens program.crespi

Shows tokens generated by the lexer:

Token { kind: Var, lexeme: "var", ... }
Token { kind: Identifier, lexeme: "x", ... }
Token { kind: Equal, lexeme: "=", ... }
...

View AST

crespi ast program.crespi

Shows the abstract syntax tree generated by the parser.

CLI Reference

Command Description
crespi <file> Run a file
crespi -c <code> Run inline code
crespi repl Start interactive REPL
crespi tokens <file> Show lexer tokens
crespi ast <file> Show syntax tree
crespi --check <file> Run type checker before execution
crespi --help Show help
crespi --version Show version

Supported Features

The interpreter supports all language features:

  • Variables and constants
  • All data types (including dictionaries)
  • Control flow: if, while, for
  • Functions and closures
  • Classes with inheritance
  • Decorators (@memoize)
  • Tail-call optimization (TCO)

When to Use the Interpreter

Use Case Recommendation
Development and testing ✅ Interpreter
Learning the language ✅ Interpreter
Quick scripts ✅ Interpreter
Using dictionaries ✅ Interpreter (only option)
Distributing executables ❌ Use compiler
Maximum performance ❌ Use compiler

See Also