bpo-35079: Revise difflib.SequenceManager.get_matching_blocks doc (GH-10144)
Specify that blocks are non-overlapping. Change '!=' to '<'.
diff --git a/Doc/library/difflib.rst b/Doc/library/difflib.rst
index 6743bdc..f044cb2 100644
--- a/Doc/library/difflib.rst
+++ b/Doc/library/difflib.rst
@@ -457,14 +457,15 @@
.. method:: get_matching_blocks()
- Return list of triples describing matching subsequences. Each triple is of
- the form ``(i, j, n)``, and means that ``a[i:i+n] == b[j:j+n]``. The
+ Return list of triples describing non-overlapping matching subsequences.
+ Each triple is of the form ``(i, j, n)``,
+ and means that ``a[i:i+n] == b[j:j+n]``. The
triples are monotonically increasing in *i* and *j*.
The last triple is a dummy, and has the value ``(len(a), len(b), 0)``. It
is the only triple with ``n == 0``. If ``(i, j, n)`` and ``(i', j', n')``
are adjacent triples in the list, and the second is not the last triple in
- the list, then ``i+n != i'`` or ``j+n != j'``; in other words, adjacent
+ the list, then ``i+n < i'`` or ``j+n < j'``; in other words, adjacent
triples always describe non-adjacent equal blocks.
.. XXX Explain why a dummy is used!
diff --git a/Misc/NEWS.d/next/Library/2018-10-26-22-53-16.bpo-35079.Tm5jvF.rst b/Misc/NEWS.d/next/Library/2018-10-26-22-53-16.bpo-35079.Tm5jvF.rst
new file mode 100644
index 0000000..33f6dc4
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-10-26-22-53-16.bpo-35079.Tm5jvF.rst
@@ -0,0 +1,2 @@
+Improve difflib.SequenceManager.get_matching_blocks doc by adding 'non-
+overlapping' and changing '!=' to '<'.