Flow generic of type {} is incompatible with default value of {}
Flow reports that a default argument value of {} is incompatible with a generic of type {}.
Here is a minimal example:
function copy<T: {}>(o: T = {}): T {
// ^ object literal [1] is incompatible with `T` [2].
return {
...o
};
}
The docs say about the type {}:
Sometimes it is useful to write types that accept arbitrary objects,
for those you should write {}.
So in what sense are they incompatible?
flowtype
edited Nov 15 '18 at 10:40
Alex
3,500722
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
add a comment |
Flow reports that a default argument value of {} is incompatible with a generic of type {}.
Here is a minimal example:
function copy<T: {}>(o: T = {}): T {
// ^ object literal [1] is incompatible with `T` [2].
return {
...o
};
}
The docs say about the type {}:
Sometimes it is useful to write types that accept arbitrary objects,
for those you should write {}.
So in what sense are they incompatible?
flowtype
edited Nov 15 '18 at 10:40
Alex
3,500722
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
add a comment |
Flow reports that a default argument value of {} is incompatible with a generic of type {}.
Here is a minimal example:
function copy<T: {}>(o: T = {}): T {
// ^ object literal [1] is incompatible with `T` [2].
return {
...o
};
}
The docs say about the type {}:
Sometimes it is useful to write types that accept arbitrary objects,
for those you should write {}.
So in what sense are they incompatible?
flowtype
edited Nov 15 '18 at 10:40
Alex
3,500722
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
Flow reports that a default argument value of {} is incompatible with a generic of type {}.
Here is a minimal example:
function copy<T: {}>(o: T = {}): T {
// ^ object literal [1] is incompatible with `T` [2].
return {
...o
};
}
The docs say about the type {}:
Sometimes it is useful to write types that accept arbitrary objects,
for those you should write {}.
So in what sense are they incompatible?
flowtype
flowtype
edited Nov 15 '18 at 10:40
Alex
3,500722
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
edited Nov 15 '18 at 10:40
Alex
3,500722
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
edited Nov 15 '18 at 10:40
Alex
3,500722
edited Nov 15 '18 at 10:40
Alex
3,500722
edited Nov 15 '18 at 10:40
Alex
3,500722
3,500722
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
asked Nov 14 '18 at 10:45
robCrobC
1,6011219
1,6011219
add a comment |
add a comment |
1 Answer
1
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oldest
votes
T: {} means "T is any subtype of {}", or in other words, T is an object type. If it has any required properties, {} is not a value of type T.
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
add a comment |
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1 Answer
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T: {} means "T is any subtype of {}", or in other words, T is an object type. If it has any required properties, {} is not a value of type T.
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
add a comment |
T: {} means "T is any subtype of {}", or in other words, T is an object type. If it has any required properties, {} is not a value of type T.
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
add a comment |
T: {} means "T is any subtype of {}", or in other words, T is an object type. If it has any required properties, {} is not a value of type T.
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
T: {} means "T is any subtype of {}", or in other words, T is an object type. If it has any required properties, {} is not a value of type T.
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
answered Nov 16 '18 at 13:04
Alexey RomanovAlexey Romanov
109k26214355
109k26214355
add a comment |
add a comment |
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