diff --git a/src/util/range.ahk b/src/util/range.ahk
index eed94ed..bc37af4 100644
--- a/src/util/range.ahk
+++ b/src/util/range.ahk
@@ -1,31 +1,44 @@
-; ###incomplete###
 range(param_start:=0,param_end:=0,param_step:=1) {
 	if (!this.isNumber(param_start) || !this.isNumber(param_end) || !this.isNumber(param_step)) {
 		this._internal_ThrowException()
 	}
 
 	; prepare
-	return_array := []
+	l_array := []
+	; A step of -1 is used if a negative start is specified without an end or step.
+	if (param_start < 0 && param_end == 0 && param_step == 1) {
+		param_step := -1
+	}
 	if (param_start == 0 && param_end == 0) {
-		return return_array
+		return l_array
 	}
 	if (param_end == 0) {
 		param_end := param_start
 		param_start := 0
 	}
 	l_currentStep := param_start
+	if (param_end > param_start) {
+		l_negativeFlag := true
+	}
+	; where step is 0, end at the array count
+	if (param_step == 0) {
+		zeroStepFlag := true
+	}
+
 
 	; create
-	while (param_start <= param_end || param_start == param_end) {
-		return_array.push(l_currentStep)
-		if (param_step == 0) {
-			param_start += 1
-		} else {
-			param_start += param_step
+	if (zeroStepFlag == true) {
+		loop, % param_end - 1 {
+			l_array.push(l_currentStep)
+			l_currentStep += param_step
+		}
+	} else {
+		while (l_currentStep != param_end) {
+			l_array.push(l_currentStep)
 			l_currentStep += param_step
 		}
 	}
-	return return_array
+	return l_array
 }
 
 
diff --git a/src/util/range.md b/src/util/range.md
new file mode 100644
index 0000000..83f7517
--- /dev/null
+++ b/src/util/range.md
@@ -0,0 +1,11 @@
+Creates an array of numbers (positive and/or negative) progressing from start up to, but not including, end. A step of -1 is used if a negative start is specified without an end or step. If end is not specified, it's set to start with start then set to 0. The array's size is used as the end when a step of 0 is specified.
+
+
+## Arguments
+[start:=0] (number): The start of the range.
+end (number): The end of the range.
+[step:=1] (number): The value to increment or decrement by.
+
+
+## Returns
+(Array): Returns the range of numbers.