diff --git a/package.json b/package.json
index 3cc6f6f..3ea0715 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "asajs",
-	"version": "4.0.4-preview",
+	"version": "4.0.5-indev",
 	"description": "Create your Minecraft JSON-UI resource packs using JavaScript",
 	"keywords": [
 		"Minecraft",
diff --git a/src/compilers/bindings/Function.ts b/src/compilers/bindings/Function.ts
index 987ea62..3b99b2e 100644
--- a/src/compilers/bindings/Function.ts
+++ b/src/compilers/bindings/Function.ts
@@ -68,6 +68,10 @@ export const defaultFunctions = {
 
 		return {
 			genBindings: [
+				{
+					source: `(${input} < 0)`,
+					target: isNegative,
+				},
 				{
 					source: `(${input} < 2)`,
 					target: isLowerThanTwo,
@@ -109,9 +113,30 @@ export const defaultFunctions = {
 		}
 	},
 
-	// str_length: str => {
-	// 	if (!/\#\w+/.test(str)) throw new Error("Invalid string")
-	// }
+	strlen: str => {
+		if (!/\#\w+/.test(str)) throw new Error("Invalid string")
+
+		const count = RandomBindingString()
+		const inputStr = RandomBindingString()
+
+		return {
+			genBindings: [
+				{
+					source: `0 * (${str} = 'a')`,
+					target: count,
+				},
+				{
+					source: `'a' + ${str}`,
+					target: inputStr,
+				},
+				{
+					source: `${count} + (not ((('%.' + (${count} + 1) + 's') * ${inputStr}) = ${inputStr}))`,
+					target: count,
+				},
+			],
+			value: count,
+		}
+	},
 
 	/**
 	 * Return a translatable string
@@ -120,6 +145,7 @@ export const defaultFunctions = {
 	 */
 	translatable: key => {
 		return {
+			genBindings: [],
 			value: `'%' + ${key}`,
 		}
 	},