README: rewrite it, it was rather out-of-date

[sage.d.git] / mjo / symbol_sequence.py

diff --git a/mjo/symbol_sequence.py b/mjo/symbol_sequence.py
index b7c438fa02fda1702f6df4fd5a6f1b3a41fce7b0..2a104aed958d877103e1962f1ad212e2ab07c981 100644 (file)
--- a/mjo/symbol_sequence.py
+++ b/mjo/symbol_sequence.py
@@ -1,7 +1,7 @@
 from sage.all import *
 
 class SymbolSequence:
-    """
+    r"""
     An iterable object which acts like a sequence of symbolic
     expressions (variables).
 
@@ -44,7 +44,7 @@ class SymbolSequence:
 
     Using a different latex name since 'lambda' is reserved::
 
-        sage: l = SymbolSequence('l', '\lambda')
+        sage: l = SymbolSequence('l', r'\lambda')
         sage: l[0]
         l_0
         sage: latex(l[0])
@@ -57,7 +57,7 @@ class SymbolSequence:
         a_0_1_2
         sage: latex(a[0,1,2])
         a_{0}_{1}_{2}
-        sage: [ a[i,j] for i in range(0,2) for j in range(0,2) ]
+        sage: [ a[i,j] for i in range(2) for j in range(2) ]
         [a_0_0, a_0_1, a_1_0, a_1_1]
 
     You can pass slices instead of integers to obtain a list of
@@ -175,9 +175,10 @@ class SymbolSequence:
         result = []
 
         for item in l:
-            if isinstance(item, list):
+            try:
+                item = iter(item)
                 result += self._flatten_list_(item)
-            else:
+            except TypeError:
                 result += [item]
 
         return result
@@ -332,7 +333,7 @@ class SymbolSequence:
                    for w in v )
 
             # This might be nested...
-            maybe_nested_list = [ s._subscript_tuple_(args) for s in ss ]
+            maybe_nested_list = ( s._subscript_tuple_(args) for s in ss )
             return self._flatten_list_(maybe_nested_list)
 
         else: