update: advanced funcs

27-functions-advanced/03-func-to-func/main.go

@@ -7,7 +7,11 @@
 
 package main
 
-import "fmt"
+import (
+	"fmt"
+	"strings"
+	"unicode"
+)
 
 type filterFunc func(int) bool
 
@@ -23,6 +27,17 @@ func main() {
 	fmt.Println("\n••• FUNC VALUES •••")
 	fmt.Printf("evens      : %d\n", filter(isEven, nums...))
 	fmt.Printf("odds       : %d\n", filter(isOdd, nums...))
+
+	fmt.Println("\n••• MAPPING •••")
+	fmt.Println(strings.Map(unpunct, "hello!!! HOW ARE YOU???? :))"))
+	fmt.Println(strings.Map(unpunct, "TIME IS UP!"))
+}
+
+func unpunct(r rune) rune {
+	if unicode.IsPunct(r) {
+		return -1
+	}
+	return unicode.ToLower(r)
 }
 
 func filter(f filterFunc, nums ...int) (filtered []int) {
@@ -33,6 +48,7 @@ func filter(f filterFunc, nums ...int) (filtered []int) {
 	}
 	return
 }
+
 func filterOdds(nums ...int) (filtered []int) {
 	for _, n := range nums {
 		if isOdd(n) {

27-functions-advanced/04-closures/main.go

@@ -22,7 +22,7 @@ func main() {
 
 	// ========================================================================
 
-	fmt.Println("\n••• FUNC LITERALS •••")
+	fmt.Println("\n••• CLOSURES •••")
 
 	var min int
 	greaterThan := func(n int) bool {
@@ -35,16 +35,29 @@ func main() {
 	min = 6
 	fmt.Printf("> 6        : %d\n", filter(greaterThan, nums...))
 
-	// ========================================================================
+	// min = 1
+	// fmt.Printf("> 1        : %d\n", filter(greaterThan, nums...))
+	// min = 2
+	// fmt.Printf("> 2        : %d\n", filter(greaterThan, nums...))
+	// min = 3
+	// fmt.Printf("> 3        : %d\n", filter(greaterThan, nums...))
 
-	fmt.Println("\n••• HIGHER-ORDER FUNCS •••")
-	fmt.Printf("> 3        : %d\n", filter(greater(3), nums...))
-	fmt.Printf("> 6        : %d\n", filter(greater(6), nums...))
+	var filterers []filterFunc
+	for i := 1; i <= 3; i++ {
+		current := i
+
+		filterers = append(filterers, func(n int) bool {
+			min = current
+			return greaterThan(n)
+		})
+	}
+
+	printer(filterers, nums...)
 }
 
-func greater(min int) filterFunc {
-	return func(n int) bool {
-		return n > min
+func printer(filterers []filterFunc, nums ...int) {
+	for i, filterer := range filterers {
+		fmt.Printf("> %d        : %d\n", i+1, filter(filterer, nums...))
 	}
 }
 

27-functions-advanced/05-higher-order-funcs/main.go

@@ -40,7 +40,7 @@ func main() {
 	fmt.Printf("dups uniqs : %v\n", filter(uniques(), out...))
 
 	dups = reverse(uniques())
-	chained := chain(reverse(greater(2)), dups, uniques())
+	chained := chain(reverse(greater(1)), dups, uniques())
 	fmt.Printf("dups chain : %v\n", filter(chained, 1, 1, 2, 3, 3, 3, 3, 0, 0))
 }
 
@@ -78,6 +78,12 @@ func greater(min int) filterFunc {
 	}
 }
 
+func lesseq(max int) filterFunc {
+	return func(n int) bool {
+		return n <= max
+	}
+}
+
 func filter(f filterFunc, nums ...int) (filtered []int) {
 	for _, n := range nums {
 		if f(n) {
@@ -89,9 +95,3 @@ func filter(f filterFunc, nums ...int) (filtered []int) {
 
 func isEven(n int) bool { return n%2 == 0 }
 func isOdd(m int) bool  { return m%2 == 1 }
-
-func lesseq(max int) filterFunc {
-	return func(n int) bool {
-		return n <= max
-	}
-}