initial publication

examples/hasflag.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"fmt"
+)
+
+const anetNone uint8 = 0
+const (
+	anetPreRel uint8 = 1 << iota
+	anetUnstable
+	anetExperiment
+
+	anetBeta  = anetPreRel | anetUnstable
+	anetAlpha = anetBeta | anetExperiment
+)
+
+var (
+	// In Golang, a byte is exactly equivalent to a uint8.
+	// Use the same value extracted in the example `extractversion.go`.
+	// A value of 0x01 (1) indicates Pre-Release flag is set, with no other myFlags set.
+	myFlags byte = 0x01
+)
+
+func main() {
+
+	fmt.Printf("Flags:\t%d\t%#02x\n\n", myFlags, myFlags)
+	// Prints:
+	/*
+		Flags:  1       0x01
+
+	*/
+
+	for flag, flagNm := range map[uint8]string{
+		anetPreRel:     "Pre-release",
+		anetUnstable:   "Unstable",
+		anetExperiment: "Experimental",
+		anetBeta:       "Beta release",
+		anetAlpha:      "Alpha release",
+	} {
+		fmt.Printf(
+			"Has flag '%s' (%d, %#02x):\t%v\n\n",
+			flagNm, flag, flag, myFlags&flag == flag,
+		)
+	}
+	// Prints:
+	/*
+		Flags:  1       0x01
+
+		Has flag 'Pre-release' (1, 0x01):       true
+
+		Has flag 'Unstable' (2, 0x02):  false
+
+		Has flag 'Experimental' (4, 0x04):      false
+
+		Has flag 'Beta release' (3, 0x03):      false
+
+		Has flag 'Alpha release' (7, 0x07):     false
+	*/
+}