Add Bind #126 (#128)

README.md

@@ -171,6 +171,7 @@ Type manipulation helpers:
 - Empty
 - IsEmpty
 - Coalesce
+- Bind
 
 Concurrency helpers:
 
@@ -1466,6 +1467,16 @@ result, ok := lo.Coalesce[*string](nil, nilStr, &str)
 // &"foobar" true
 ```
 
+### Bind
+
+Returns new function that, when called, has its first argument set to the provided value.
+```go
+add := func(x, y int) int { return x + y }
+f := Bind(add, 5)
+f(10)
+// 15
+```
+
 ### Attempt
 
 Invokes a function N times until it returns valid output. Returning either the caught error or nil. When first argument is less than `1`, the function runs until a successful response is returned.

func.go

@@ -0,0 +1,8 @@
+package lo
+
+// Bind returns new function that, when called, has its first argument set to the provided value.
+func Bind[T1, T2, R any](f func(T1, T2) R, arg1 T1) func(T2) R {
+	return func(t2 T2) R {
+		return f(arg1, t2)
+	}
+}

func_test.go

@@ -0,0 +1,16 @@
+package lo
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestBind(t *testing.T) {
+	is := assert.New(t)
+
+	add := func(x, y int) int { return x + y }
+	f := Bind(add, 5)
+	is.Equal(15, f(10))
+	is.Equal(0, f(-5))
+}