From: Scott Gasch <scott@gasch.org>
Date: Fri, 24 Sep 2021 17:03:18 +0000 (-0700)
Subject: Trie repr.
X-Git-Url: https://wannabe.guru.org/gitweb/?a=commitdiff_plain;h=0338feb616bee4ba7bcd3b51748c4b79569cca0f;p=python_utils.git

Trie repr.
---

diff --git a/trie.py b/trie.py
index be7a48d..b9a5a1a 100644
--- a/trie.py
+++ b/trie.py
@@ -13,7 +13,7 @@ class Trie(object):
     """
     def __init__(self):
         self.root = {}
-        self.end = "~#END#~"
+        self.end = "~END~"
         self.length = 0
 
     def insert(self, item: Sequence[Any]):
@@ -90,7 +90,7 @@ class Trie(object):
         >>> t.insert('tessera')
         >>> t.insert('tesack')
         >>> t['tes']
-        {'t': {'~#END#~': '~#END#~', 'i': {'c': {'l': {'e': {'~#END#~': '~#END#~'}}}}}, 's': {'e': {'r': {'a': {'~#END#~': '~#END#~'}}}}, 'a': {'c': {'k': {'~#END#~': '~#END#~'}}}}
+        {'t': {'~END~': '~END~', 'i': {'c': {'l': {'e': {'~END~': '~END~'}}}}}, 's': {'e': {'r': {'a': {'~END~': '~END~'}}}}, 'a': {'c': {'k': {'~END~': '~END~'}}}}
 
         """
         ret = self.__traverse__(item)
@@ -125,12 +125,12 @@ class Trie(object):
         >>> len(t)
         3
         >>> t.root
-        {'t': {'e': {'s': {'t': {'~#END#~': '~#END#~'}, 's': {'~#END#~': '~#END#~', 'e': {'l': {'~#END#~': '~#END#~'}}}}}}}
+        {'t': {'e': {'s': {'t': {'~END~': '~END~'}, 's': {'~END~': '~END~', 'e': {'l': {'~END~': '~END~'}}}}}}}
         >>> t.__delitem__('test')
         >>> len(t)
         2
         >>> t.root
-        {'t': {'e': {'s': {'s': {'~#END#~': '~#END#~', 'e': {'l': {'~#END#~': '~#END#~'}}}}}}}
+        {'t': {'e': {'s': {'s': {'~END~': '~END~', 'e': {'l': {'~END~': '~END~'}}}}}}}
         >>> for x in t:
         ...     print(x)
         tess
@@ -139,7 +139,7 @@ class Trie(object):
         >>> len(t)
         1
         >>> t.root
-        {'t': {'e': {'s': {'s': {'~#END#~': '~#END#~'}}}}}
+        {'t': {'e': {'s': {'s': {'~END~': '~END~'}}}}}
         >>> for x in t:
         ...     print(x)
         tess
@@ -240,6 +240,53 @@ class Trie(object):
             return None
         return [x for x in node if x != self.end]
 
+    def repr_recursive(self, node, delimiter):
+        """
+        A friendly string representation of the contents of the Trie.
+
+        >>> t = Trie()
+        >>> t.insert([10, 0, 0, 1])
+        >>> t.insert([10, 0, 0, 2])
+        >>> t.insert([10, 10, 10, 1])
+        >>> t.insert([10, 10, 10, 2])
+        >>> t.repr_recursive(t.root, '.')
+        '10.[0.0.[1, 2], 10.10.[1, 2]]'
+        >>> print(t)
+        10[00[1, 2], 1010[1, 2]]
+
+        """
+        child_count = 0
+        my_rep = ''
+        for child in node:
+            if child != self.end:
+                child_count += 1
+                child_rep = self.repr_recursive(node[child], delimiter)
+                if len(child_rep) > 0:
+                    my_rep += str(child) + delimiter + child_rep + ", "
+                else:
+                    my_rep += str(child) + ", "
+        if len(my_rep) > 1:
+            my_rep = my_rep[:-2]
+        if child_count > 1:
+            my_rep = f'[{my_rep}]'
+        return my_rep
+
+    def __repr__(self):
+        """
+        A friendly string representation of the contents of the Trie.  Under
+        the covers uses repr_recursive with no delimiter
+
+        >>> t = Trie()
+        >>> t.insert([10, 0, 0, 1])
+        >>> t.insert([10, 0, 0, 2])
+        >>> t.insert([10, 10, 10, 1])
+        >>> t.insert([10, 10, 10, 2])
+        >>> print(t)
+        10[00[1, 2], 1010[1, 2]]
+
+        """
+        return self.repr_recursive(self.root, '')
+
 
 if __name__ == '__main__':
     import doctest