4.5 KiB
		
	
	
	
	
	
	
	
			
		
		
	
	
			4.5 KiB
		
	
	
	
	
	
	
	
The Tengo Language
Tengo is a small, dynamic, fast, secure script language for Go.
Tengo is fast and secure because it's compiled/executed as bytecode on stack-based VM that's written in native Go.
/* 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"
Test this Tengo code in the Tengo Playground
Features
- Simple and highly readable
Syntax
- Dynamic typing with type coercion
- Higher-order functions and closures
- Immutable values
 
- Securely Embeddable and Extensible
- Compiler/runtime written in native Go (no external deps or cgo)
- Executable as a standalone language / REPL
- Use cases: rules engine, state machine, data pipeline, transpiler
Benchmark
| fib(35) | fibt(35) | Type | |
|---|---|---|---|
| Go | 48ms | 3ms | Go (native) | 
| Tengo | 2,349ms | 5ms | VM on Go | 
| Lua | 1,416ms | 3ms | Lua (native) | 
| go-lua | 4,402ms | 5ms | Lua VM on Go | 
| GopherLua | 4,023ms | 5ms | Lua VM on Go | 
| Python | 2,588ms | 26ms | Python (native) | 
| starlark-go | 11,126ms | 6ms | Python-like Interpreter on Go | 
| gpython | 15,035ms | 4ms | Python Interpreter on Go | 
| goja | 5,089ms | 5ms | JS VM on Go | 
| otto | 68,377ms | 11ms | JS Interpreter on Go | 
| Anko | 92,579ms | 18ms | Interpreter on Go | 
* fib(35):
Fibonacci(35)
* fibt(35):
tail-call version of Fibonacci(35)
* Go does not read the source code from file, while all other cases do
* See here for commands/codes used
Quick Start
go get github.com/d5/tengo/v2
A simple Go example code that compiles/runs Tengo script code with some input/output values:
package main
import (
	"context"
	"fmt"
	"github.com/d5/tengo/v2"
)
func main() {
	// Tengo script code
	src := `
each := func(seq, fn) {
    for x in seq { fn(x) }
}
sum := 0
mul := 1
each([a, b, c, d], func(x) {
	sum += x
	mul *= x
})`
	// create a new Script instance
	script := tengo.NewScript([]byte(src))
	// set values
	_ = script.Add("a", 1)
	_ = script.Add("b", 9)
	_ = script.Add("c", 8)
	_ = script.Add("d", 4)
	// run the script
	compiled, err := script.RunContext(context.Background())
	if err != nil {
		panic(err)
	}
	// retrieve values
	sum := compiled.Get("sum")
	mul := compiled.Get("mul")
	fmt.Println(sum, mul) // "22 288"
}
 
			