From f6f25c9192d029862d9d0f97f1e02c07896e62b2 Mon Sep 17 00:00:00 2001
From: Tom Wiesing <tkw01536@gmail.com>
Date: Thu, 21 May 2020 14:34:34 +0200
Subject: [PATCH 1/2] Convert range() objects using 'integer_interval' from cd
 'interval1'

This issue adds translation for the range() class to the
DefaultConverter. Note that a python range(start, stop) does not include
the value of stop, whereas the 'integer_interval' symbol does. The
converter thus has to add or subtract one.

Fixes #29.
---
 openmath/convert.py   | 9 +++++++++
 tests/test_convert.py | 1 +
 2 files changed, 10 insertions(+)

diff --git a/openmath/convert.py b/openmath/convert.py
index 5074e23..f59bda9 100644
--- a/openmath/convert.py
+++ b/openmath/convert.py
@@ -259,6 +259,7 @@ class BasicPythonConverter(Converter):
     - complex numbers (recursively),
     - strings,
     - bytes,
+    - ranges,
     - lists (recursively),
     - sets (recursively).
     """
@@ -278,6 +279,8 @@ def __init__(self):
         r('set1', 'set', lambda *args: set(args))
         r('list1', 'list', lambda *args: list(args))
         r('complex1', 'complex_cartesian', complex) # this does not work if the arguments are not numbers
+        r('interval1', 'integer_interval', lambda x,y: range(x, y + 1, 1))
+
         # literals
         s = self.register_to_python_class
         s(om.OMInteger, lambda o: o.integer)
@@ -311,6 +314,12 @@ def do_set(s):
             else:
                 return oms('emptyset', cd='set1')
         t(set, do_set)
+        def do_range(r):
+            if r.step != 1:
+                raise ValueError('Cannot convert %r to OpenMath: Range must have a step of 1. ' % obj)
+            return om.OMApplication(oms('integer_interval', 'interval1'), [om.OMInteger(r.start), om.OMInteger(r.stop - 1)])
+        t(range, do_range)
+
 
 
 # A default converter instance for convenience
diff --git a/tests/test_convert.py b/tests/test_convert.py
index 13708c0..2f6f86b 100644
--- a/tests/test_convert.py
+++ b/tests/test_convert.py
@@ -15,6 +15,7 @@ def test_py_om_py(self):
             "", "test",
             [], [1,2,3],
             set(), set([1,2,3]),
+            range(1, 12)
         ]
         for obj in testcases:
             conv = DefaultConverter.to_python(DefaultConverter.to_openmath(obj))

From c0387695631c6ec0dac1361aae5ed6e0578cbd0a Mon Sep 17 00:00:00 2001
From: Tom Wiesing <tkw1536@users.noreply.github.com>
Date: Fri, 22 May 2020 13:34:57 +0200
Subject: [PATCH 2/2] Update README with range() conversion

---
 README.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/README.rst b/README.rst
index f54b863..674c0cb 100644
--- a/README.rst
+++ b/README.rst
@@ -66,6 +66,7 @@ By default, a ``Converter`` only implements conversions for basic Python types:
 - complex numbers,
 - strings,
 - bytes,
+- ranges,
 - lists (recursively),
 - sets (recursively).