drop python 2.5 support

nltk/__init__.py

@@ -15,9 +15,7 @@
 Natural Language Processing with Python.  O'Reilly Media Inc.
 http://nltk.org/book
 """
-
-# python2.5 compatibility
-from __future__ import with_statement, print_function, absolute_import
+from __future__ import print_function, absolute_import
 
 import os
 
@@ -52,7 +50,7 @@
 # Description of the toolkit, keywords, and the project's primary URL.
 __longdescr__ = """\
 The Natural Language Toolkit (NLTK) is a Python package for
-natural language processing.  NLTK requires Python 2.5 or higher."""
+natural language processing.  NLTK requires Python 2.6 or higher."""
 __keywords__ = ['NLP', 'CL', 'natural language processing',
                 'computational linguistics', 'parsing', 'tagging',
                 'tokenizing', 'syntax', 'linguistics', 'language',
@@ -74,7 +72,6 @@
     'Intended Audience :: Science/Research',
     'License :: OSI Approved :: Apache Software License',
     'Operating System :: OS Independent',
-    'Programming Language :: Python :: 2.5',
     'Programming Language :: Python :: 2.6',
     'Programming Language :: Python :: 2.7',
     'Topic :: Scientific/Engineering',
@@ -111,11 +108,7 @@
 from .tree import *
 from .util import *
 from .yamltags import *
-
-# Modules that require Python 2.6
-from sys import version_info as vi
-if vi[0] == 2 and vi[1] >= 6:
-    from .align import *
+from .align import *
 
 # don't import contents into top-level namespace:
 

nltk/corpus/reader/lin.py

@@ -5,8 +5,6 @@
 # URL: <http://www.nltk.org/>
 # For license information, see LICENSE.txt
 
-from __future__ import with_statement
-
 import re
 from collections import defaultdict
 

nltk/downloader.py

@@ -62,7 +62,7 @@
 
     python nltk/downloader.py [-d DATADIR] [-q] [-f] [-k] PACKAGE_IDS
 
-or with py2.5+:
+or::
 
     python -m nltk.downloader [-d DATADIR] [-q] [-f] [-k] PACKAGE_IDS
 """

nltk/sem/chat80.py

@@ -384,27 +384,23 @@ def cities2table(filename, rel_name, dbname, verbose=False, setup=False):
     :param dbname: filename of persistent store
     :type schema: str
     """
-    try:
-        import sqlite3
-        records = _str2records(filename, rel_name)
-        connection =  sqlite3.connect(dbname)
-        cur = connection.cursor()
-        if setup:
-            cur.execute('''CREATE TABLE city_table
-            (City text, Country text, Population int)''')
-
-        table_name = "city_table"
-        for t in records:
-            cur.execute('insert into %s values (?,?,?)' % table_name, t)
-            if verbose:
-                print "inserting values into %s: " % table_name, t
-        connection.commit()
+    import sqlite3
+    records = _str2records(filename, rel_name)
+    connection =  sqlite3.connect(dbname)
+    cur = connection.cursor()
+    if setup:
+        cur.execute('''CREATE TABLE city_table
+        (City text, Country text, Population int)''')
+
+    table_name = "city_table"
+    for t in records:
+        cur.execute('insert into %s values (?,?,?)' % table_name, t)
         if verbose:
-            print "Committing update to %s" % dbname
-        cur.close()
-    except ImportError:
-        import warnings
-        warnings.warn("To run this function, first install pysqlite, or else use Python 2.5 or later.")
+            print "inserting values into %s: " % table_name, t
+    connection.commit()
+    if verbose:
+        print "Committing update to %s" % dbname
+    cur.close()
 
 def sql_query(dbname, query):
     """
@@ -422,10 +418,6 @@ def sql_query(dbname, query):
         connection.text_factory = sqlite3.OptimizedUnicode
         cur = connection.cursor()
         return cur.execute(query)
-    except ImportError:
-        import warnings
-        warnings.warn("To run this function, first install pysqlite, or else use Python 2.5 or later.")
-        raise
     except ValueError:
         import warnings
         warnings.warn("Make sure the database file %s is installed and uncompressed." % dbname)
@@ -777,15 +769,10 @@ def sql_demo():
     """
     Print out every row from the 'city.db' database.
     """
-    try:
-        import sqlite3
-        print
-        print "Using SQL to extract rows from 'city.db' RDB."
-        for row in sql_query('corpora/city_database/city.db', "SELECT * FROM city_table"):
-            print row
-    except ImportError:
-        import warnings
-        warnings.warn("To run the SQL demo, first install pysqlite, or else use Python 2.5 or later.")
+    print
+    print "Using SQL to extract rows from 'city.db' RDB."
+    for row in sql_query('corpora/city_database/city.db', "SELECT * FROM city_table"):
+        print row
 
 
 if __name__ == '__main__':

nltk/tag/hunpos.py

@@ -49,7 +49,6 @@ class HunposTagger(TaggerI):
     .. doctest::
         :options: +SKIP
 
-        >>> from __future__ import with_statement # python2.5 compat
         >>> with HunposTagger('english.model') as ht:
         ...     ht.tag('What is the airspeed of an unladen swallow ?'.split())
         ...

setup.py

@@ -56,7 +56,6 @@
     'Intended Audience :: Science/Research',
     'License :: OSI Approved :: Apache Software License',
     'Operating System :: OS Independent',
-    'Programming Language :: Python :: 2.5',
     'Programming Language :: Python :: 2.6',
     'Programming Language :: Python :: 2.7',
     'Topic :: Scientific/Engineering',

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py25,py26,py27,py32,pypy
+envlist = py26,py27,py32,pypy
 
 [testenv]
 

web/install.rst

@@ -1,7 +1,7 @@
 Installing NLTK
 ===============
 
-NLTK requires Python versions 2.5-2.7.
+NLTK requires Python versions 2.6-2.7.
 
 Mac/Unix
 --------