8000 Add the 'Iterator' protocol · packetloop/haskell-cpython@8b1ad2c · GitHub
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Add the 'Iterator' protocol
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Original file line numberDiff line numberDiff line change
@@ -56,10 +56,20 @@ module CPython.Internal
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, checkIntReturn
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-- * Other classes
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-- ** Mapping
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, Mapping (..)
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, SomeMapping (..)
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, unsafeCastToMapping
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-- ** Sequence
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, Sequence (..)
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, SomeSequence (..)
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, unsafeCastToSequence
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-- ** Iterator
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, Iterator (..)
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, SomeIterator (..)
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, unsafeCastToIterator
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) where
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import Control.Applicative ((<$>))
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import qualified Control.Exception as E
@@ -208,7 +218,51 @@ data SomeMapping = forall a. (Mapping a) => SomeMapping (ForeignPtr a)
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class Object a => Mapping a where
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toMapping :: a -> SomeMapping
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instance Object SomeMapping where
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toObject (SomeMapping x) = SomeObject x
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fromForeignPtr = SomeMapping
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instance Mapping SomeMapping where
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toMapping = id
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unsafeCastToMapping :: Object a => a -> SomeMapping
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unsafeCastToMapping x = case toObject x of
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SomeObject ptr -> let
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ptr' = castForeignPtr ptr :: ForeignPtr SomeMapping
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in SomeMapping ptr'
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data SomeSequence = forall a. (Sequence a) => SomeSequence (ForeignPtr a)
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class Object a => Sequence a where
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toSequence :: a -> SomeSequence
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instance Object SomeSequence where
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toObject (SomeSequence x) = SomeObject x
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fromForeignPtr = SomeSequence
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instance Sequence SomeSequence where
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toSequence = id
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unsafeCastToSequence :: Object a => a -> SomeSequence
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unsafeCastToSequence x = case toObject x of
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SomeObject ptr -> let
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ptr' = castForeignPtr ptr :: ForeignPtr SomeSequence
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in SomeSequence ptr'
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data SomeIterator = forall a. (Iterator a) => SomeIterator (ForeignPtr a)
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class Object a => Iterator a where
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toIterator :: a -> SomeIterator
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instance Object SomeIterator where
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toObject (SomeIterator x) = SomeObject x
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fromForeignPtr = SomeIterator
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instance Iterator SomeIterator where
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toIterator = id
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unsafeCastToIterator :: Object a => a -> SomeIterator
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unsafeCastToIterator x = case toObject x of
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SomeObject ptr -> let
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ptr' = castForeignPtr ptr :: ForeignPtr SomeIterator
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in SomeIterator ptr'
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,50 @@
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-- Copyright (C) 2009 John Millikin <jmillikin@gmail.com>
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--
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-- This program is free software: you can redistribute it and/or modify
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-- it under the terms of the GNU General Public License as published by
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-- the Free Software Foundation, either version 3 of the License, or
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-- any later version.
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--
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-- This program is distributed in the hope that it will be useful,
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-- but WITHOUT ANY WARRANTY; without even the implied warranty of
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-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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-- GNU General Public License for more details.
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--
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-- You should have received a copy of the GNU General Public License
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-- along with this program. If not, see <http://www.gnu.org/licenses/>.
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--
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{-# LANGUAGE ForeignFunctionInterface #-}
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module CPython.Protocols.Iterator
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( Iterator (..)
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, SomeIterator
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, castToIterator
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, next
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) where
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import CPython.Internal
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#include <hscpython-shim.h>
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-- | Attempt to convert an object to a generic 'Iterator'. If the object does
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-- not implement the iterator protocol, returns 'Nothing'.
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--
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castToIterator :: Object a => a -> IO (Maybe SomeIterator)
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castToIterator obj =
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withObject obj $ \objPtr -> do
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isIter <- fmap cToBool $ {# call hscpython_PyIter_Check as ^ #} objPtr
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return $ if isIter
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then Just $ unsafeCastToIterator obj
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else Nothing
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-- | Return the next value from the iteration, or 'Nothing' if there are no
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-- remaining items.
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--
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next :: Iterator iter => iter -> IO (Maybe SomeObject)
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next iter =
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withObject iter $ \iterPtr -> do
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raw <- {# call PyIter_Next as ^ #} iterPtr
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if raw == nullPtr
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then do
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err <- {# call PyErr_Occurred as ^ #}
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exceptionIf $ err /= nullPtr
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return Nothing
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else fmap Just $ stealObject raw
Original file line numberDiff line numberDiff line change
@@ -31,22 +31,9 @@ import CPython.Internal
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#include <hscpython-shim.h>
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34-
instance Object SomeMapping where
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toObject (SomeMapping x) = SomeObject x
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fromForeignPtr = SomeMapping
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instance Mapping SomeMapping where
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toMapping = id
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instance Mapping Dictionary where
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toMapping = unsafeCastToMapping
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unsafeCastToMapping :: Object a => a -> SomeMapping
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unsafeCastToMapping x = case toObject x of
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SomeObject ptr -> let
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ptr' = castForeignPtr ptr :: ForeignPtr SomeMapping
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in SomeMapping ptr'
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castToMapping :: Object a => a -> IO (Maybe SomeMapping)
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castToMapping obj =
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withObject obj $ \objPtr -> do
Original file line numberDiff line numberDiff line change
@@ -45,13 +45,6 @@ import CPython.Types.Unicode (Unicode)
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#include <hscpython-shim.h>
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48-
instance Object SomeSequence where
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toObject (SomeSequence x) = SomeObject x
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fromForeignPtr = SomeSequence
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52-
instance Sequence SomeSequence where
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toSequence = id
54-
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instance Sequence ByteArray where
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toSequence = unsafeCastToSequence
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@@ -67,12 +60,6 @@ instance Sequence Tuple where
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instance Sequence Unicode where
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toSequence = unsafeCastToSequence
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unsafeCastToSequence :: Object a => a -> SomeSequence
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unsafeCastToSequence x = case toObject x of
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SomeObject ptr -> let
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ptr' = castForeignPtr ptr :: ForeignPtr SomeSequence
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in SomeSequence ptr'
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-- | Attempt to convert an object to a generic 'Sequence'. If the object does
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-- not implement the sequence protocol, returns 'Nothing'.
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--
Original file line numberDiff line numberDiff line change
@@ -30,7 +30,6 @@ module CPython.Types
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, CPython.Types.Integer.Integer
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, SequenceIterator
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, CallableIterator
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, Iterator
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, List
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, Method
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, Module
Original file line numberDiff line numberDiff line change
@@ -15,26 +15,23 @@
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--
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{-# LANGUAGE ForeignFunctionInterface #-}
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module CPython.Types.Iterator
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( Iterator
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, SequenceIterator
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( SequenceIterator
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, sequenceIteratorType
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, sequenceIteratorNew
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, CallableIterator
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, callableIteratorType
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, callableIteratorNew
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, next
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) where
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import CPython.Internal
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#include <hscpython-shim.h>
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33-
class Object a => Iterator a
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3530
newtype SequenceIterator = SequenceIterator (ForeignPtr SequenceIterator)
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37-
instance Iterator SequenceIterator
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instance Iterator SequenceIterator where
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toIterator = unsafeCastToIterator
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instance Object SequenceIterator where
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toObject (SequenceIterator x) = SomeObject x
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fromForeignPtr = SequenceIterator
@@ -44,7 +41,9 @@ instance Concrete SequenceIterator where
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4542
newtype CallableIterator = CallableIterator (ForeignPtr CallableIterator)
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47-
instance Iterator CallableIterator
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instance Iterator CallableIterator where
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toIterator = unsafeCastToIterator
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instance Object CallableIterator where
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toObject (CallableIterator x) = SomeObject x
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fromForeignPtr = CallableIterator
@@ -58,7 +57,7 @@ instance Concrete CallableIterator where
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{# fun pure hscpython_PyCallIter_Type as callableIteratorType
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{} -> `Type' peekStaticObject* #}
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61-
-- | Return an iterator that works with a general sequence object, /seq/.
60+
-- | Return an 'Iterator' that works with a general sequence object, /seq/.
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-- The iteration ends when the sequence raises @IndexError@ for the
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-- subscripting operation.
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--
@@ -67,7 +66,7 @@ instance Concrete CallableIterator where
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{ withObject* `seq'
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} -> `SequenceIterator' stealObject* #}
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70-
-- | Return a new iterator. The first parameter, /callable/, can be any
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-- | Return a new 'Iterator'. The first parameter, /callable/, can be any
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-- Python callable object that can be called with no parameters; each call
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-- to it should return the next item in the iteration. When /callable/
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-- returns a value equal to /sentinel/, the iteration will be terminated.
@@ -77,17 +76,3 @@ instance Concrete CallableIterator where
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{ withObject* `callable'
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, withObject* `sentinel'
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} -> `CallableIterator' stealObject* #}
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-- | Return the next value from the iteration, or 'Nothing' if there are no
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-- remaining items.
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--
84-
next :: Iterator iter => iter -> IO (Maybe SomeObject)
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next iter =
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withObject iter $ \iterPtr -> do
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raw <- {# call PyIter_Next as ^ #} iterPtr
88-
if raw == nullPtr
89-
then do
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err <- {# call PyErr_Occurred as ^ #}
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exceptionIf $ err /= nullPtr
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return Nothing
93-
else fmap Just $ stealObject raw
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
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name: cpython
2-
version: 3.1.1.0
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version: 3.1.2.0
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synopsis: Bindings for libpython
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license: GPL-3
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license-file: license.txt
@@ -64,6 +64,7 @@ library
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CPython.Types.Type
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CPython.Types.Unicode
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CPython.Types.WeakReference
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CPython.Protocols.Iterator
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CPython.Protocols.Mapping
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CPython.Protocols.Number
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CPython.Protocols.Object
Original file line numberDiff line numberDiff line change
@@ -59,6 +59,9 @@ int hscpython_PyObject_DelAttr(PyObject *o, PyObject *name)
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int hscpython_PyObject_TypeCheck (PyObject *o, PyTypeObject *type)
6060
{ return PyObject_TypeCheck (o, type); }
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62+
int hscpython_PyIter_Check(PyObject *o)
63+
{ return PyIter_Check(o); }
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6265
/* Types */
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PyTypeObject *hscpython_PyType_Type ()
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{ return &PyType_Type; }
Original file line numberDiff line numberDiff line change
@@ -12,6 +12,7 @@ void hscpython_Py_INCREF (PyObject *);
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void hscpython_Py_DECREF (PyObject *);
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int hscpython_PyObject_DelAttr(PyObject *, PyObject *);
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int hscpython_PyObject_TypeCheck (PyObject *, PyTypeObject *);
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int hscpython_PyIter_Check(PyObject *);
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enum HSCPythonComparisonEnum
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{ HSCPYTHON_LT = Py_LT