<p align="center"> <img src="https://raw.githubusercontent.com/d5/tengolang.com/master/logo_400.png" width="200" height="200"> </p> # The Tengo Language [![GoDoc](https://godoc.org/github.com/d5/tengo?status.svg)](https://godoc.org/github.com/d5/tengo/script) [![Go Report Card](https://goreportcard.com/badge/github.com/d5/tengo)](https://goreportcard.com/report/github.com/d5/tengo) [![Build Status](https://travis-ci.org/d5/tengo.svg?branch=master)](https://travis-ci.org/d5/tengo) **Tengo is a small, dynamic, fast, secure script language for Go.** Tengo is **[fast](#benchmark)** and secure because it's compiled/executed as bytecode on stack-based VM that's written in native Go. ```golang /* The Tengo Language */ fmt := import("fmt") each := func(seq, fn) { for x in seq { fn(x) } } sum := func(init, seq) { each(seq, func(x) { init += x }) return init } fmt.println(sum(0, [1, 2, 3])) // "6" fmt.println(sum("", [1, 2, 3])) // "123" ``` > Run this code in the [Playground](https://tengolang.com/?s=0c8d5d0d88f2795a7093d7f35ae12c3afa17bea3) ## Features - Simple and highly readable [Syntax](https://github.com/d5/tengo/blob/master/docs/tutorial.md) - Dynamic typing with type coercion - Higher-order functions and closures - Immutable values - Garbage collection - [Securely Embeddable](https://github.com/d5/tengo/blob/master/docs/interoperability.md) and [Extensible](https://github.com/d5/tengo/blob/master/docs/objects.md) - Compiler/runtime written in native Go _(no external deps or cgo)_ - Executable as a [standalone](https://github.com/d5/tengo/blob/master/docs/tengo-cli.md) language / REPL - Use cases: rules engine, [state machine](https://github.com/d5/go-fsm), [gaming](https://github.com/d5/pbr), data pipeline, [transpiler](https://github.com/d5/tengo2lua) ## Benchmark | | fib(35) | fibt(35) | Type | | :--- | ---: | ---: | :---: | | Go | `48ms` | `3ms` | Go (native) | | [**Tengo**](https://github.com/d5/tengo) | `2,349ms` | `5ms` | VM on Go | | Lua | `1,416ms` | `3ms` | Lua (native) | | [go-lua](https://github.com/Shopify/go-lua) | `4,402ms` | `5ms` | Lua VM on Go | | [GopherLua](https://github.com/yuin/gopher-lua) | `4,023ms` | `5ms` | Lua VM on Go | | Python | `2,588ms` | `26ms` | Python (native) | | [starlark-go](https://github.com/google/starlark-go) | `11,126ms` | `6ms` | Python-like Interpreter on Go | | [gpython](https://github.com/go-python/gpython) | `15,035ms` | `4ms` | Python Interpreter on Go | | [goja](https://github.com/dop251/goja) | `5,089ms` | `5ms` | JS VM on Go | | [otto](https://github.com/robertkrimen/otto) | `68,377ms` | `11ms` | JS Interpreter on Go | | [Anko](https://github.com/mattn/anko) | `92,579ms` | `18ms` | Interpreter on Go | _* [fib(35)](https://github.com/d5/tengobench/blob/master/code/fib.tengo): Fibonacci(35)_ _* [fibt(35)](https://github.com/d5/tengobench/blob/master/code/fibtc.tengo): [tail-call](https://en.wikipedia.org/wiki/Tail_call) version of Fibonacci(35)_ _* **Go** does not read the source code from file, while all other cases do_ _* See [here](https://github.com/d5/tengobench) for commands/codes used_ ## References - [Language Syntax](https://github.com/d5/tengo/blob/master/docs/tutorial.md) - [Object Types](https://github.com/d5/tengo/blob/master/docs/objects.md) - [Runtime Types](https://github.com/d5/tengo/blob/master/docs/runtime-types.md) and [Operators](https://github.com/d5/tengo/blob/master/docs/operators.md) - [Builtin Functions](https://github.com/d5/tengo/blob/master/docs/builtins.md) - [Interoperability](https://github.com/d5/tengo/blob/master/docs/interoperability.md) - [Tengo CLI](https://github.com/d5/tengo/blob/master/docs/tengo-cli.md) - [Standard Library](https://github.com/d5/tengo/blob/master/docs/stdlib.md)