Modern String Formatting in Code (aimacode#292)

* Modern string formatting in csp.py.

* Modern string formatting in games.py.

* Modern string formatting in learning.py.

* Modern string formatting in nlp.py.

* Modern string formatting in probability.py.

* Modern string formatting in search.py.

* Replaced {0\!r} by {} if %s.

* Corrected a typo.

Author: sampadsaha5

csp.py

@@ -344,7 +344,7 @@ def __init__(self, value): self.value = value
 
     def __getitem__(self, key): return self.value
 
-    def __repr__(self): return '{Any: %r}' % self.value
+    def __repr__(self): return '{{Any: {0!r}}}'.format(self.value)
 
 
 def different_values_constraint(A, a, B, b):

games.py

@@ -203,7 +203,7 @@ def display(self, state):
         print(state)
 
     def __repr__(self):
-        return '<%s>' % self.__class__.__name__
+        return '<{}>'.format(self.__class__.__name__)
 
 
 class Fig52Game(Game):

learning.py

@@ -139,8 +139,8 @@ def check_example(self, example):
         if self.values:
             for a in self.attrs:
                 if example[a] not in self.values[a]:
-                    raise ValueError('Bad value %s for attribute %s in %s' %
-                                     (example[a], self.attrnames[a], example))
+                    raise ValueError('Bad value {} for attribute {} in {}'
+                                     .format(example[a], self.attrnames[a], example))
 
     def attrnum(self, attr):
         "Returns the number used for attr, which can be a name, or -n .. n-1."
@@ -157,7 +157,7 @@ def sanitize(self, example):
                 for i, attr_i in enumerate(example)]
 
     def __repr__(self):
-        return '<DataSet(%s): %d examples, %d attributes>' % (
+        return '<DataSet({}): {:d} examples, {:d} attributes>'.format(
             self.name, len(self.examples), len(self.attrs))
 
 # ______________________________________________________________________________
@@ -317,8 +317,8 @@ def display(self, indent=0):
             subtree.display(indent + 1)
 
     def __repr__(self):
-        return ('DecisionFork(%r, %r, %r)'
-                % (self.attr, self.attrname, self.branches))
+        return ('DecisionFork({0!r}, {1!r}, {2!r})'
+                .format(self.attr, self.attrname, self.branches))
 
 
 class DecisionLeaf:
@@ -771,9 +771,9 @@ def test(predict, dataset, examples=None, verbose=0):
         if output == desired:
             right += 1
             if verbose >= 2:
-                print('   OK: got %s for %s' % (desired, example))
+                print('   OK: got {} for {}'.format(desired, example))
         elif verbose:
-            print('WRONG: got %s, expected %s for %s' % (
+            print('WRONG: got {}, expected {} for {}'.format(
                 output, desired, example))
     return 1 - (right / len(examples))
 

nlp.py

@@ -52,7 +52,7 @@ def isa(self, word, cat):
         return cat in self.categories[word]
 
     def __repr__(self):
-        return '<Grammar %s>' % self.name
+        return '<Grammar {}>'.format(self.name)
 
 E0 = Grammar('E0',
              Rules(  # Grammar for E_0 [Figure 22.4]
@@ -158,7 +158,7 @@ def add_edge(self, edge):
         if edge not in self.chart[end]:
             self.chart[end].append(edge)
             if self.trace:
-                print('Chart: added %s' % (edge,))
+                print('Chart: added {}'.format(edge))
             if not expects:
                 self.extender(edge)
             else:

probability.py

@@ -80,7 +80,7 @@ def show_approx(self, numfmt='%.3g'):
                           for (v, p) in sorted(self.prob.items())])
 
     def __repr__(self):
-        return "P(%s)" % self.varname
+        return "P({})".format(self.varname)
 
 
 class JointProbDist(ProbDist):
@@ -117,7 +117,7 @@ def values(self, var):
         return self.vals[var]
 
     def __repr__(self):
-        return "P(%s)" % self.variables
+        return "P({})".format(self.variables)
 
 
 def event_values(event, variables):
@@ -192,14 +192,14 @@ def variable_node(self, var):
         for n in self.nodes:
             if n.variable == var:
                 return n
-        raise Exception("No such variable: %s" % var)
+        raise Exception("No such variable: {}".format(var))
 
     def variable_values(self, var):
         "Return the domain of var."
         return [True, False]
 
     def __repr__(self):
-        return 'BayesNet(%r)' % self.nodes
+        return 'BayesNet({0!r})'.format(self.nodes)
 
 
 class BayesNode:

search.py

@@ -96,7 +96,7 @@ def __init__(self, state, parent=None, action=None, path_cost=0):
             self.depth = parent.depth + 1
 
     def __repr__(self):
-        return "<Node %s>" % (self.state,)
+        return "<Node {}>".format(self.state)
 
     def __lt__(self, node):
         return self.state < node.state
@@ -1133,7 +1133,7 @@ def __getattr__(self, attr):
         return getattr(self.problem, attr)
 
     def __repr__(self):
-        return '<%4d/%4d/%4d/%s>' % (self.succs, self.goal_tests,
+        return '<{:4d}/{:4d}/{:4d}/{}>'.format(self.succs, self.goal_tests,
                                      self.states, str(self.found)[:4])