TS1238: Unable to resolve signature of class decorator when called as an expression

I am seeing the following compilation error:

TS1238: Unable to resolve signature of class decorator when called as
an expression.

Here is the code:

const fdec = function(target:any, field: any, desc: any)
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function()
 console.log('target 1:');
 return function(target:any, field: any, desc: any)
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

Does anyone know how to fix that error?

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

add a comment |

I am seeing the following compilation error:

TS1238: Unable to resolve signature of class decorator when called as
an expression.

Here is the code:

const fdec = function(target:any, field: any, desc: any)
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function()
 console.log('target 1:');
 return function(target:any, field: any, desc: any)
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

Does anyone know how to fix that error?

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

add a comment |

I am seeing the following compilation error:

TS1238: Unable to resolve signature of class decorator when called as
an expression.

Here is the code:

const fdec = function(target:any, field: any, desc: any)
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function()
 console.log('target 1:');
 return function(target:any, field: any, desc: any)
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

Does anyone know how to fix that error?

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

I am seeing the following compilation error:

TS1238: Unable to resolve signature of class decorator when called as
an expression.

Here is the code:

const fdec = function(target:any, field: any, desc: any)
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function()
 console.log('target 1:');
 return function(target:any, field: any, desc: any)
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

Does anyone know how to fix that error?

typescript tsc typescript3.0

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

asked Nov 15 '18 at 8:10

Alexander Mills

19.6k33159340

add a comment |

1 Answer
1

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The signature for a class decorator (as ou can find in lib.d.ts) has to be the following:

declare type ClassDecorator = <TFunction extends Function>(target: TFunction) => TFunction | void;

So your class decorator can't have a field and desc parameter (or they should be optional if you plan to use the decorator as a field decorator as well)

const fdec = function (target: any) 
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function () 
 console.log('target 1:');
 return function (target: any) 
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

add a comment |

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1 Answer
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1 Answer
1

active

oldest

votes

The signature for a class decorator (as ou can find in lib.d.ts) has to be the following:

declare type ClassDecorator = <TFunction extends Function>(target: TFunction) => TFunction | void;

So your class decorator can't have a field and desc parameter (or they should be optional if you plan to use the decorator as a field decorator as well)

const fdec = function (target: any) 
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function () 
 console.log('target 1:');
 return function (target: any) 
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

add a comment |

The signature for a class decorator (as ou can find in lib.d.ts) has to be the following:

declare type ClassDecorator = <TFunction extends Function>(target: TFunction) => TFunction | void;

So your class decorator can't have a field and desc parameter (or they should be optional if you plan to use the decorator as a field decorator as well)

const fdec = function (target: any) 
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function () 
 console.log('target 1:');
 return function (target: any) 
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

add a comment |

The signature for a class decorator (as ou can find in lib.d.ts) has to be the following:

declare type ClassDecorator = <TFunction extends Function>(target: TFunction) => TFunction | void;

So your class decorator can't have a field and desc parameter (or they should be optional if you plan to use the decorator as a field decorator as well)

const fdec = function (target: any) 
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function () 
 console.log('target 1:');
 return function (target: any) 
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

The signature for a class decorator (as ou can find in lib.d.ts) has to be the following:

declare type ClassDecorator = <TFunction extends Function>(target: TFunction) => TFunction | void;

So your class decorator can't have a field and desc parameter (or they should be optional if you plan to use the decorator as a field decorator as well)

const fdec = function (target: any) 
 console.log('target 0 :', target);
 target.bar = 3;
 return target;
;

const fdec2 = function () 
 console.log('target 1:');
 return function (target: any) 
 console.log('target 2:', target);
 target.bar = 3;
 return target;
 
;

@fdec
@fdec2()
class Foo 
 static bar: number



console.log(Foo.bar);
console.log(new Foo());

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

answered Nov 15 '18 at 8:17

Titian Cernicova-Dragomir

69.3k34865

add a comment |

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