Lazy property is initialized twice
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0
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As we all know lazy property is not thread safe.
my evaluation part is like this.
if someclass isInitialized {
return someclass instance
}
else{
initialize someclass
return someclass instance
}
The problem is
If thread 1 sees that someclass is not initialised it will then try to do so.
If thread 2 sees that someclass is not initialised before thread 1 gets to do so, then it too will try to initialise it too.
so it is initialized twice
can we overcome this with lazy property?
swift lazy-evaluation lazy-initialization
asked Nov 21 at 7:35
Naveen Paulsingh
244
add a comment |
up vote
0
down vote
favorite
As we all know lazy property is not thread safe.
my evaluation part is like this.
if someclass isInitialized {
return someclass instance
}
else{
initialize someclass
return someclass instance
}
The problem is
If thread 1 sees that someclass is not initialised it will then try to do so.
If thread 2 sees that someclass is not initialised before thread 1 gets to do so, then it too will try to initialise it too.
so it is initialized twice
can we overcome this with lazy property?
swift lazy-evaluation lazy-initialization
asked Nov 21 at 7:35
Naveen Paulsingh
244
Have a look at stackoverflow.com/questions/24024549/… and developer.apple.com/documentation/swift/cocoa_design_patterns/…, it shows how to use static properties to (lazily) instantiate shared instances (or other resources) in a thread-safe way.
– Martin R
Nov 21 at 7:39
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
As we all know lazy property is not thread safe.
my evaluation part is like this.
if someclass isInitialized {
return someclass instance
}
else{
initialize someclass
return someclass instance
}
The problem is
If thread 1 sees that someclass is not initialised it will then try to do so.
If thread 2 sees that someclass is not initialised before thread 1 gets to do so, then it too will try to initialise it too.
so it is initialized twice
can we overcome this with lazy property?
swift lazy-evaluation lazy-initialization
asked Nov 21 at 7:35
Naveen Paulsingh
244
As we all know lazy property is not thread safe.
my evaluation part is like this.
if someclass isInitialized {
return someclass instance
}
else{
initialize someclass
return someclass instance
}
The problem is
If thread 1 sees that someclass is not initialised it will then try to do so.
If thread 2 sees that someclass is not initialised before thread 1 gets to do so, then it too will try to initialise it too.
so it is initialized twice
can we overcome this with lazy property?
swift lazy-evaluation lazy-initialization
swift lazy-evaluation lazy-initialization
asked Nov 21 at 7:35
Naveen Paulsingh
244
asked Nov 21 at 7:35
Naveen Paulsingh
244
asked Nov 21 at 7:35
Naveen Paulsingh
244
asked Nov 21 at 7:35
Naveen Paulsingh
244
asked Nov 21 at 7:35
Naveen Paulsingh
244
244
Have a look at stackoverflow.com/questions/24024549/… and developer.apple.com/documentation/swift/cocoa_design_patterns/…, it shows how to use static properties to (lazily) instantiate shared instances (or other resources) in a thread-safe way.
– Martin R
Nov 21 at 7:39
add a comment |
Have a look at stackoverflow.com/questions/24024549/… and developer.apple.com/documentation/swift/cocoa_design_patterns/…, it shows how to use static properties to (lazily) instantiate shared instances (or other resources) in a thread-safe way.
– Martin R
Nov 21 at 7:39
Have a look at stackoverflow.com/questions/24024549/… and developer.apple.com/documentation/swift/cocoa_design_patterns/…, it shows how to use static properties to (lazily) instantiate shared instances (or other resources) in a thread-safe way.
– Martin R
Nov 21 at 7:39
Have a look at stackoverflow.com/questions/24024549/… and developer.apple.com/documentation/swift/cocoa_design_patterns/…, it shows how to use static properties to (lazily) instantiate shared instances (or other resources) in a thread-safe way.
– Martin R
Nov 21 at 7:39
add a comment |
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Have a look at stackoverflow.com/questions/24024549/… and developer.apple.com/documentation/swift/cocoa_design_patterns/…, it shows how to use static properties to (lazily) instantiate shared instances (or other resources) in a thread-safe way.
– Martin R
Nov 21 at 7:39