diff --git a/src/cbaselib.c b/src/cbaselib.c
index 7776836..0b6bc01 100644
--- a/src/cbaselib.c
+++ b/src/cbaselib.c
@@ -110,6 +110,22 @@ int cosmoB_loadstring(CState *state, int nargs, CValue *args) {
     return 2; // <boolean>, <closure> or <error>
 }
 
+int cosmoB_error(CState *state, int nargs, CValue *args) {
+    if (nargs < 1) {
+        cosmoV_error(state, "error() expected 1 argument, got %d!", nargs);
+        return 0;
+    }
+
+    if (!IS_STRING(args[0])) {
+        cosmoV_typeError(state, "error()", "<string>", "%s", cosmoV_typeStr(args[0]));
+        return 0;
+    }
+
+    cosmoV_error(state, "%s", cosmoV_readCString(args[0]));
+
+    return 0;
+}
+
 void cosmoB_loadLibrary(CState *state) {
     const char *identifiers[] = {
         "print",
@@ -118,7 +134,8 @@ void cosmoB_loadLibrary(CState *state) {
         "pcall",
         "tonumber",
         "tostring",
-        "loadstring"
+        "loadstring",
+        "error"
     };
 
     CosmoCFunction baseLib[] = {
@@ -128,7 +145,8 @@ void cosmoB_loadLibrary(CState *state) {
         cosmoB_pcall,
         cosmoB_tonumber,
         cosmoB_tostring,
-        cosmoB_loadstring
+        cosmoB_loadstring,
+        cosmoB_error
     };
 
     int i;
@@ -492,13 +510,30 @@ int cosmoB_sChar(CState *state, int nargs, CValue *args) {
     return 1;
 }
 
+int cosmoB_sLen(CState *state, int nargs, CValue *args) {
+    if (nargs < 1) {
+        cosmoV_error(state, "string.len() expected 1 argument, got %d", nargs);
+        return 0;
+    }
+
+    if (!IS_STRING(args[0])) {
+        cosmoV_typeError(state, "string.len", "<string>", "%s", cosmoV_typeStr(args[0]));
+        return 0;
+    }
+
+    cosmoV_pushNumber(state, strlen(cosmoV_readCString(args[0])));
+
+    return 1;
+}
+
 void cosmoB_loadStrLib(CState *state) {
     const char *identifiers[] = {
         "sub",
         "find",
         "split",
         "byte",
-        "char"
+        "char",
+        "len"
     };
 
     CosmoCFunction strLib[] = {
@@ -506,7 +541,8 @@ void cosmoB_loadStrLib(CState *state) {
         cosmoB_sFind,
         cosmoB_sSplit,
         cosmoB_sByte,
-        cosmoB_sChar
+        cosmoB_sChar,
+        cosmoB_sLen
     };
 
     // make string library object
diff --git a/src/cobj.h b/src/cobj.h
index 6a77a6f..b5fde5f 100644
--- a/src/cobj.h
+++ b/src/cobj.h
@@ -120,6 +120,7 @@ typedef struct CObjUpval {
 #define IS_CLOSURE(x)   isObjType(x, COBJ_CLOSURE)
 
 #define cosmoV_readString(x)    ((CObjString*)cosmoV_readRef(x))
+#define cosmoV_readCString(x)   (((CObjString*)cosmoV_readRef(x))->str)
 #define cosmoV_readObject(x)    ((CObjObject*)cosmoV_readRef(x))
 #define cosmoV_readTable(x)     ((CObjTable*)cosmoV_readRef(x))
 #define cosmoV_readFunction(x)  ((CObjFunction*)cosmoV_readRef(x))