[#16] Use better parameter names (#17)

Closes #16

bit_methods.go

@@ -1,21 +1,21 @@
 package gobits
 
-// ContainsBit test if a bit (position b) is contains in a
-func ContainsBit(a byte, b uint8) bool {
-	return ContainsBits(a, SetBit(0x00, b))
+// ContainsBit test if a bit is contains in the data
+func ContainsBit(data byte, bit uint8) bool {
+	return ContainsBits(data, SetBit(0x00, bit))
 }
 
-// SetBit change the bit (b) of a to 1
-func SetBit(a byte, b uint8) byte {
-	return SetBits(a, 0x01<<b)
+// SetBit change the bit of the data to 1
+func SetBit(data byte, bit uint8) byte {
+	return SetBits(data, 0x01<<bit)
 }
 
-// UnsetBit change the bit (b) of a to 0
-func UnsetBit(a byte, b uint8) byte {
-	return UnsetBits(a, 0x01<<b)
+// UnsetBit change the bit of the data to 0
+func UnsetBit(data byte, bit uint8) byte {
+	return UnsetBits(data, 0x01<<bit)
 }
 
-// GetBit get the bit from a byte
-func GetBit(a byte, b uint8) byte {
-	return (a >> b & 0x01) << b
+// GetBit get the bit value from the data
+func GetBit(data byte, bit uint8) byte {
+	return (data >> bit & 0x01) << bit
 }

bits_methods.go

@@ -1,22 +1,22 @@
 package gobits
 
 // ContainsBits test if b is contains in a
-func ContainsBits(a, b byte) bool {
-	return a&b == b
+func ContainsBits(data, bits byte) bool {
+	return data&bits == bits
 }
 
 // SetBits affect to a, the b bits
-func SetBits(a, b byte) byte {
-	return a | b
+func SetBits(data, bits byte) byte {
+	return data | bits
 }
 
 // UnsetBits unaffect to a, the b bits
-func UnsetBits(a, b byte) byte {
-	return a &^ b
+func UnsetBits(data, bits byte) byte {
+	return data &^ bits
 }
 
 // ExtractBits get a byte for subset of another byte
-func ExtractBits(a byte, b, c uint8) byte {
-	var unusedBits = 7 + b - c
-	return a >> b << unusedBits >> unusedBits
+func ExtractBits(data byte, lsb, msb uint8) byte {
+	var unusedBits = 7 + msb - lsb
+	return data >> msb << unusedBits >> unusedBits
 }

bits_methods_test.go

@@ -26,7 +26,7 @@ func TestUnsetBits(t *testing.T) {
 }
 
 func TestExtractBits(t *testing.T) {
-	var result = ExtractBits(0xDA, 3, 4)
+	var result = ExtractBits(0xDA, 4, 3)
 	if result != 0x03 {
 		t.Errorf("ExtractBits don't work: %08b", result)
 	}