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nstd (The Non-Standard Go library)

nstd is a single-package go module which provides some missing types and functions in the standard library.

Project page: https://github.com/go101/nstd

Module path: go101.org/nstd

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Some examples using nstd

Example 1:
package main

import (
	"go101.org/nstd"
	"log"
)

const debug = true

const foo = "foo"

func debugPrint(s string) {
	if debug {
		log.Print(s)
	}
}

func main() {
	var bar = "bar"
	_ = debug && nstd.Logf(foo + ":" + bar)
	// It is cleaner than
	//    if debug {
	//         log.Print(foo + " " + bar)
	//    }
	//
	// And it is more performant than
	//    debugPrint(foo + " " + bar)
	// when debug is false.
}

Example 2:
package main

import (
	"go101.org/nstd"
)

func ExampleMutexAndWaitGroup() {
	const N = 1000
	var n = 0
	defer func() {
		nstd.Printfln("n = %d", n) // will print a new line at the end
		if expected := N*7; n != expected {
			nstd.Panicf("n (%d) != %d", n, expected) // panic with format
		}
	}()

	var wg nstd.WaitGroup
	defer wg.Wait()

	var m nstd.Mutex
	for range [1000]struct{}{} {
		// WaitGroup.Go starts several tasks.
		wg.Go(func() {
			defer m.Lock().Unlock() // call Lock and Unlock chainly
			n += 2
		}, func() {
			defer m.Lock().Unlock()
			n += 1
		})
		
		// WaitGroup.GoN starts one task several times.
		wg.GoN(3, func() {
			defer m.Lock().Unlock()
			n += 1
		})
	}

	// Mutex.Do guards the execution of a function.
	m.Do(func() {
		n += N
	})
}

func main() {
	ExampleMutexAndWaitGroup()
}

Example 3:
package main

import (
	"go101.org/nstd"
)

func main() {
	pInt := nstd.New(123)
	nstd.Printfln("%T: %v", pInt, *pInt) // *int: 123
	pBool := nstd.New(true)
	nstd.Printfln("%T: %v", pBool, *pBool) // *bool: true

	nstd.Printfln("%v", nstd.Zero[int]())  // 0
	nstd.Printfln("%v", nstd.Zero[bool]()) // false

	nstd.Printfln("%v", nstd.Zero(789))  // 0
	nstd.Printfln("%v", nstd.Zero(true)) // false

	nstd.ZeroIt(pInt)
	nstd.Printfln("%v", *pInt) // 0
	nstd.ZeroIt(pBool)
	nstd.Printfln("%v", *pBool) // false
}

Example 4:
package main

import (
	"go101.org/nstd"
)

func main() {
	var aCondition = true
	
	var m = map[string]int{"Zig": 2016}
	_ = aCondition && nstd.HasEntry(m, "Go")
	// So that, no need to write it in two lines:
	//     _, ok := m["Go"]
	//     _ = aCondition && ok
	
	var x any = 123
	var n int
	_ = aCondition && nstd.TypeAssert(x, &n)
	// So that, no need to write it in two lines:
	//     n, ok := x.(int)
	//      _ = aCondition && ok
	nstd.Printfln("n = %v", n) // n = 123
	_ = aCondition && nstd.TypeAssert[int](x, nil)
	_ = aCondition && nstd.TypeAssert(x, (*int)(nil))
}

Example 5:
package main

import (
	"reflect"
	"go101.org/nstd"
)

func main() {
	var n int = 123
	var x any = n
	
	nstd.Printfln("type of x: %s", reflect.TypeOf(x)) // type of x: int
	nstd.Printfln("type of x: %s", nstd.TypeOf(x))    // type of x: interface {}
	
	nstd.Printfln("type of x: %s", reflect.ValueOf(x).Type()) // type of x: int
	nstd.Printfln("type of x: %s", nstd.ValueOf(x).Type())    // type of x: interface {}
}


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