diff --git a/mapytex/calculus/core/random/leaf.py b/mapytex/calculus/core/random/leaf.py
index fdf0815..802bd17 100644
--- a/mapytex/calculus/core/random/leaf.py
+++ b/mapytex/calculus/core/random/leaf.py
@@ -9,6 +9,46 @@
 """
 
 """
+from ..coroutine import *
+
+
+@coroutine
+def look_for_rdleaf(target):
+    """ Coroutine which look to "{...}" which are RdLeaf
+
+    :example:
+    >>> from ..str2 import list_sink
+    >>> str2list = look_for_rdleaf(list_sink)
+    >>> for i in "{a}+{a*b}-2":
+    ...    str2list.send(i)
+    >>> a = str2list.throw(STOOOP)
+    >>> a
+    [<RdLeaf a>, '+', <RdLeaf a*b>, '-', '2']
+
+    """
+    try:
+        target_ = target()
+    except TypeError:
+        target_ = target
+
+    try:
+        while True:
+            tok = yield
+            if tok == "{":
+                stack = ""
+                stacking = True
+            elif tok == "}":
+                target_.send(RdLeaf(stack))
+                stack = ""
+                stacking = False
+            else:
+                if stacking:
+                    stack += tok
+                else:
+                    target_.send(tok)
+
+    except STOOOP as err:
+        yield target_.throw(err)
 
 
 class RdLeaf:
@@ -25,10 +65,10 @@ class RdLeaf:
         return self._name
 
     def replace(self, computed):
-        return computed[self.name]
+        return computed[self._name]
 
     def __str__(self):
-        return "{" + self.name + "}"
+        return "{" + self._name + "}"
 
     def __repr__(self):
-        return f"<{self.__class__.__name__} {self.__str__}>"
+        return f"<{self.__class__.__name__} {self._name}>"
diff --git a/mapytex/calculus/core/str2.py b/mapytex/calculus/core/str2.py
index 7ba8772..672ac10 100644
--- a/mapytex/calculus/core/str2.py
+++ b/mapytex/calculus/core/str2.py
@@ -15,6 +15,7 @@ from decimal import Decimal, InvalidOperation
 from .coroutine import *
 from .operator import is_operator
 from .MO import moify
+from .random.leaf import look_for_rdleaf
 
 __all__ = ["str2"]
 
@@ -476,7 +477,7 @@ def lookforNumbers(target):
             if tok is not None:
                 try:
                     int(tok)
-                except ValueError:
+                except (ValueError, TypeError):
                     if tok == ".":
                         if current.replace("-", "", 1).isdigit():
                             current += tok
@@ -497,7 +498,7 @@ def lookforNumbers(target):
                         else:
                             try:
                                 target_.send(typifiy_numbers(current))
-                            except InvalidOperation:
+                            except (InvalidOperation, TypeError):
                                 target_.send(current)
                             target_.send("+")
                             current = tok
@@ -511,7 +512,7 @@ def lookforNumbers(target):
                         else:
                             try:
                                 target_.send(typifiy_numbers(current))
-                            except InvalidOperation:
+                            except (InvalidOperation, TypeError):
                                 target_.send(current)
                             current = tok
                 else:
@@ -530,7 +531,7 @@ def lookforNumbers(target):
         if current:
             try:
                 target_.send(typifiy_numbers(current))
-            except InvalidOperation:
+            except (InvalidOperation, TypeError):
                 target_.send(current)
         yield target_.throw(err)
 
@@ -605,7 +606,7 @@ def list_sink():
 
 
 def str2(sink, convert_to_mo=True):
-    """ Return a pipeline which parse an expression with the sink as an endpont
+    """ Return a pipeline which parse an expression with the sink as an endpoint
 
     :example:
 
@@ -810,6 +811,31 @@ def str2(sink, convert_to_mo=True):
     return pipeline
 
 
+def rdstr2(sink):
+    """ Return a pipeline which parse random expression and with sink as endpoint
+
+    :example:
+    >>> rdstr2list = rdstr2(list_sink)
+    >>> rdstr2list("{a}+{a*b}-2")
+    [<RdLeaf a>, '+', <RdLeaf a*b>, '+', <MOnumber - 2>]
+    """
+    lfop = lookfor(is_operator)
+    operator_corout = partial(concurent_broadcast, lookfors=[lfop])
+
+    def pipeline(expression):
+        str2_corout = look_for_rdleaf(
+            lookforNumbers(operator_corout(missing_times(moify(pparser(sink)))))
+        )
+
+        for i in expression.replace(" ", ""):
+            str2_corout.send(i)
+        a = str2_corout.throw(STOOOP)
+
+        return a
+
+    return pipeline
+
+
 str2nestedlist = str2(list_sink)