python generator does not work as my expectation
0
class ObjA(object):
def __init__(self, self_id):
self.id = self_id
self.sub_items =
def __str__(self):
return "objA{id=%d;sub_items=%s}" % (self.id, str(self.sub_items))
__repr__ = __str__
lst =
a1 = ObjA(1)
a1.sub_items.append(1)
a1.sub_items.append(2)
a2 = ObjA(2)
a2.sub_items.append(3)
lst.append(a1)
lst.append(a2)
result = {a.id: {tmp: a} for a in lst for tmp in a.sub_items}
print result
the result is:
{1: {2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
but i want it like:
{1: {1: objA{id=1;sub_items=[1, 2]},
2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
something is wrong.
python
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
asked Nov 26 '18 at 5:30
王小敏王小敏
31
add a comment |
0
class ObjA(object):
def __init__(self, self_id):
self.id = self_id
self.sub_items =
def __str__(self):
return "objA{id=%d;sub_items=%s}" % (self.id, str(self.sub_items))
__repr__ = __str__
lst =
a1 = ObjA(1)
a1.sub_items.append(1)
a1.sub_items.append(2)
a2 = ObjA(2)
a2.sub_items.append(3)
lst.append(a1)
lst.append(a2)
result = {a.id: {tmp: a} for a in lst for tmp in a.sub_items}
print result
the result is:
{1: {2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
but i want it like:
{1: {1: objA{id=1;sub_items=[1, 2]},
2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
something is wrong.
python
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
asked Nov 26 '18 at 5:30
王小敏王小敏
31
1
There are no generators in your example.
– DYZ
Nov 26 '18 at 5:38
it is actually a Dict Comprehension.
– 王小敏
Nov 26 '18 at 7:12
add a comment |
0
0
0
class ObjA(object):
def __init__(self, self_id):
self.id = self_id
self.sub_items =
def __str__(self):
return "objA{id=%d;sub_items=%s}" % (self.id, str(self.sub_items))
__repr__ = __str__
lst =
a1 = ObjA(1)
a1.sub_items.append(1)
a1.sub_items.append(2)
a2 = ObjA(2)
a2.sub_items.append(3)
lst.append(a1)
lst.append(a2)
result = {a.id: {tmp: a} for a in lst for tmp in a.sub_items}
print result
the result is:
{1: {2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
but i want it like:
{1: {1: objA{id=1;sub_items=[1, 2]},
2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
something is wrong.
python
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
asked Nov 26 '18 at 5:30
王小敏王小敏
31
class ObjA(object):
def __init__(self, self_id):
self.id = self_id
self.sub_items =
def __str__(self):
return "objA{id=%d;sub_items=%s}" % (self.id, str(self.sub_items))
__repr__ = __str__
lst =
a1 = ObjA(1)
a1.sub_items.append(1)
a1.sub_items.append(2)
a2 = ObjA(2)
a2.sub_items.append(3)
lst.append(a1)
lst.append(a2)
result = {a.id: {tmp: a} for a in lst for tmp in a.sub_items}
print result
the result is:
{1: {2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
but i want it like:
{1: {1: objA{id=1;sub_items=[1, 2]},
2: objA{id=1;sub_items=[1, 2]}},
2: {3: objA{id=2;sub_items=[3]}}};
something is wrong.
python
python
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
asked Nov 26 '18 at 5:30
王小敏王小敏
31
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
asked Nov 26 '18 at 5:30
王小敏王小敏
31
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
edited Nov 26 '18 at 5:35
DYZ
27.9k62150
27.9k62150
asked Nov 26 '18 at 5:30
王小敏王小敏
31
asked Nov 26 '18 at 5:30
王小敏王小敏
31
asked Nov 26 '18 at 5:30
王小敏王小敏
31
31
1
There are no generators in your example.
– DYZ
Nov 26 '18 at 5:38
it is actually a Dict Comprehension.
– 王小敏
Nov 26 '18 at 7:12
add a comment |
1
There are no generators in your example.
– DYZ
Nov 26 '18 at 5:38
it is actually a Dict Comprehension.
– 王小敏
Nov 26 '18 at 7:12
1
1
There are no generators in your example.
– DYZ
Nov 26 '18 at 5:38
There are no generators in your example.
– DYZ
Nov 26 '18 at 5:38
it is actually a Dict Comprehension.
– 王小敏
Nov 26 '18 at 7:12
it is actually a Dict Comprehension.
– 王小敏
Nov 26 '18 at 7:12
add a comment |
1 Answer
1
active
oldest
votes
4
The nested comprehension you are looking for is the following:
{a.id: {tmp: a for tmp in a.sub_items} for a in lst}
# {1: {1: objA{id=1;sub_items=[1, 2]},
# 2: objA{id=1;sub_items=[1, 2]}},
# 2: {3: objA{id=2;sub_items=[3]}}}
Your original version is usually used to create a flat data structure. This leads to the key 1 being assigned a twice, keeping only the second value.
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
add a comment |
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1 Answer
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active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
4
The nested comprehension you are looking for is the following:
{a.id: {tmp: a for tmp in a.sub_items} for a in lst}
# {1: {1: objA{id=1;sub_items=[1, 2]},
# 2: objA{id=1;sub_items=[1, 2]}},
# 2: {3: objA{id=2;sub_items=[3]}}}
Your original version is usually used to create a flat data structure. This leads to the key 1 being assigned a twice, keeping only the second value.
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
add a comment |
4
The nested comprehension you are looking for is the following:
{a.id: {tmp: a for tmp in a.sub_items} for a in lst}
# {1: {1: objA{id=1;sub_items=[1, 2]},
# 2: objA{id=1;sub_items=[1, 2]}},
# 2: {3: objA{id=2;sub_items=[3]}}}
Your original version is usually used to create a flat data structure. This leads to the key 1 being assigned a twice, keeping only the second value.
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
add a comment |
4
4
4
The nested comprehension you are looking for is the following:
{a.id: {tmp: a for tmp in a.sub_items} for a in lst}
# {1: {1: objA{id=1;sub_items=[1, 2]},
# 2: objA{id=1;sub_items=[1, 2]}},
# 2: {3: objA{id=2;sub_items=[3]}}}
Your original version is usually used to create a flat data structure. This leads to the key 1 being assigned a twice, keeping only the second value.
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
The nested comprehension you are looking for is the following:
{a.id: {tmp: a for tmp in a.sub_items} for a in lst}
# {1: {1: objA{id=1;sub_items=[1, 2]},
# 2: objA{id=1;sub_items=[1, 2]}},
# 2: {3: objA{id=2;sub_items=[3]}}}
Your original version is usually used to create a flat data structure. This leads to the key 1 being assigned a twice, keeping only the second value.
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
edited Nov 26 '18 at 5:42
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
answered Nov 26 '18 at 5:36
schwobasegglschwobaseggl
37.4k32442
37.4k32442
add a comment |
add a comment |
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1
There are no generators in your example.
– DYZ
Nov 26 '18 at 5:38
it is actually a Dict Comprehension.
– 王小敏
Nov 26 '18 at 7:12