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diff --git a/examples/range_check.py b/examples/range_check.py
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+++ b/examples/range_check.py
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+# rangeCheck.py
+#
+#   A sample program showing how parse actions can convert parsed
+# strings into a data type or object, and to validate the parsed value.
+#
+# Updated to use new addCondition method and expr() copy.
+#
+# Copyright 2011,2015 Paul T. McGuire
+#
+
+import pyparsing as pp
+from datetime import datetime
+
+
+def ranged_value(expr, minval=None, maxval=None):
+    # have to specify at least one range boundary
+    if minval is None and maxval is None:
+        raise ValueError("minval or maxval must be specified")
+
+    # set range testing function and error message depending on
+    # whether either or both min and max values are given
+    in_range_condition = {
+        (False, True): lambda s, l, t: t[0] <= maxval,
+        (True, False): lambda s, l, t: minval <= t[0],
+        (True, True): lambda s, l, t: minval <= t[0] <= maxval,
+    }[minval is not None, maxval is not None]
+    out_of_range_message = {
+        (False, True): f"value is greater than {maxval}",
+        (True, False): f"value is less than {minval}",
+        (True, True): f"value is not in the range ({minval} to {maxval})",
+    }[minval is not None, maxval is not None]
+
+    return expr().add_condition(in_range_condition, message=out_of_range_message)
+
+
+# define the expressions for a date of the form YYYY/MM/DD or YYYY/MM (assumes YYYY/MM/01)
+integer = pp.Word(pp.nums).set_name("integer")
+integer.set_parse_action(lambda t: int(t[0]))
+
+month = ranged_value(integer, 1, 12)
+day = ranged_value(integer, 1, 31)
+year = ranged_value(integer, 2000, None)
+
+SLASH = pp.Suppress("/")
+dateExpr = year("year") + SLASH + month("month") + pp.Opt(SLASH + day("day"))
+dateExpr.set_name("date")
+
+# convert date fields to datetime (also validates dates as truly valid dates)
+dateExpr.set_parse_action(lambda t: datetime(t.year, t.month, t.day or 1).date())
+
+# add range checking on dates
+mindate = datetime(2002, 1, 1).date()
+maxdate = datetime.now().date()
+dateExpr = ranged_value(dateExpr, mindate, maxdate)
+
+
+dateExpr.run_tests(
+    """
+    2011/5/8
+    2001/1/1
+    2004/2/29
+    2004/2
+    1999/12/31"""
+)