Typescript “Cannot find name ”
I am pretty new to TypeScript.
I have created a class with some private fields. When I attempt to assign a value to one of the fields in an anonymous callback function within a class method I get the error ...
(TS) Cannot Find the name '_tokens'
I suspect that there is a scoping issue but from my understanding of JavaScript this should not be a problem. I am not sure how to fix it. Any ideas?
See .. "populateTokens()" method for error.
class SingleSignOn {
private _appTokensURL: string = "/api/IFSessionCache/Auth/";
private _tokens: string;
/**
* Initialize an instance of the SingleSignOn class to manage the permissions for the
* application associated with the application.
*/
constructor() {
this.populateTokens();
};
/**
* Gets a list of permissions tokens associated with the currently logged on user for
* the application.
*/
private getApplicationTokens(): Q.IPromise<{}> {
return Unique.AJAX.Get(this._appTokensURL, null, ENUMS.AjaxContentTypes.JSON);
};
private populateTokens () {
this.getApplicationTokens().then(
function (data) {
_tokens = <string>data; // (TS) Cannot find name "_tokens"
});
};
};
javascript typescript
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
add a comment |
I am pretty new to TypeScript.
I have created a class with some private fields. When I attempt to assign a value to one of the fields in an anonymous callback function within a class method I get the error ...
(TS) Cannot Find the name '_tokens'
I suspect that there is a scoping issue but from my understanding of JavaScript this should not be a problem. I am not sure how to fix it. Any ideas?
See .. "populateTokens()" method for error.
class SingleSignOn {
private _appTokensURL: string = "/api/IFSessionCache/Auth/";
private _tokens: string;
/**
* Initialize an instance of the SingleSignOn class to manage the permissions for the
* application associated with the application.
*/
constructor() {
this.populateTokens();
};
/**
* Gets a list of permissions tokens associated with the currently logged on user for
* the application.
*/
private getApplicationTokens(): Q.IPromise<{}> {
return Unique.AJAX.Get(this._appTokensURL, null, ENUMS.AjaxContentTypes.JSON);
};
private populateTokens () {
this.getApplicationTokens().then(
function (data) {
_tokens = <string>data; // (TS) Cannot find name "_tokens"
});
};
};
javascript typescript
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
1
There are several question about this error on Stack Overflow. Do any of those help you?
– Heretic Monkey
Nov 13 '18 at 14:32
add a comment |
I am pretty new to TypeScript.
I have created a class with some private fields. When I attempt to assign a value to one of the fields in an anonymous callback function within a class method I get the error ...
(TS) Cannot Find the name '_tokens'
I suspect that there is a scoping issue but from my understanding of JavaScript this should not be a problem. I am not sure how to fix it. Any ideas?
See .. "populateTokens()" method for error.
class SingleSignOn {
private _appTokensURL: string = "/api/IFSessionCache/Auth/";
private _tokens: string;
/**
* Initialize an instance of the SingleSignOn class to manage the permissions for the
* application associated with the application.
*/
constructor() {
this.populateTokens();
};
/**
* Gets a list of permissions tokens associated with the currently logged on user for
* the application.
*/
private getApplicationTokens(): Q.IPromise<{}> {
return Unique.AJAX.Get(this._appTokensURL, null, ENUMS.AjaxContentTypes.JSON);
};
private populateTokens () {
this.getApplicationTokens().then(
function (data) {
_tokens = <string>data; // (TS) Cannot find name "_tokens"
});
};
};
javascript typescript
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
I am pretty new to TypeScript.
I have created a class with some private fields. When I attempt to assign a value to one of the fields in an anonymous callback function within a class method I get the error ...
(TS) Cannot Find the name '_tokens'
I suspect that there is a scoping issue but from my understanding of JavaScript this should not be a problem. I am not sure how to fix it. Any ideas?
See .. "populateTokens()" method for error.
class SingleSignOn {
private _appTokensURL: string = "/api/IFSessionCache/Auth/";
private _tokens: string;
/**
* Initialize an instance of the SingleSignOn class to manage the permissions for the
* application associated with the application.
*/
constructor() {
this.populateTokens();
};
/**
* Gets a list of permissions tokens associated with the currently logged on user for
* the application.
*/
private getApplicationTokens(): Q.IPromise<{}> {
return Unique.AJAX.Get(this._appTokensURL, null, ENUMS.AjaxContentTypes.JSON);
};
private populateTokens () {
this.getApplicationTokens().then(
function (data) {
_tokens = <string>data; // (TS) Cannot find name "_tokens"
});
};
};
javascript typescript
javascript typescript
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
asked Nov 13 '18 at 14:25
Gary O. StenstromGary O. Stenstrom
1,03152549
1,03152549
1
There are several question about this error on Stack Overflow. Do any of those help you?
– Heretic Monkey
Nov 13 '18 at 14:32
add a comment |
1
There are several question about this error on Stack Overflow. Do any of those help you?
– Heretic Monkey
Nov 13 '18 at 14:32
1
1
There are several question about this error on Stack Overflow. Do any of those help you?
– Heretic Monkey
Nov 13 '18 at 14:32
There are several question about this error on Stack Overflow. Do any of those help you?
– Heretic Monkey
Nov 13 '18 at 14:32
add a comment |
3 Answers
3
active
oldest
votes
You are using the wrong syntax:
this.getApplicationTokens().then(
(data) => {
this._tokens = <string>data; // note: turned into an arrow function and added the `this` keyword
});
note if you kept using function() ... syntax the this keyword will not point to the class instance but to the callee
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
greetings
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
add a comment |
Properties of a class do not have a scope, they live as long as the object they belong to live and everything that can access the object can access all its properties too. However properties always have to be accessed on their object, e.g. something._tokens or this._tokens inside methods. Also you have to make sure that this is what you think it is, in your case you have to use an arrow function to access the correct this inside a callback:
this.getApplicationTokens().then( (data) => {
this._tokens = data as string;
});
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
Thanks. I have not learned much/anything about arrow functions! Also for the helpful link!
– Gary O. Stenstrom
Nov 13 '18 at 14:39
add a comment |
I think you're just missing the this keyword from _tokens:
this._tokens = <string>data;
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
answered Nov 13 '18 at 14:30
KCM78KCM78
34
this is not enough, the OP also has to change the callback function into an arrow function, otherwisethiswill not point to the classes instance
– messerbill
Nov 13 '18 at 14:35
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
You are using the wrong syntax:
this.getApplicationTokens().then(
(data) => {
this._tokens = <string>data; // note: turned into an arrow function and added the `this` keyword
});
note if you kept using function() ... syntax the this keyword will not point to the class instance but to the callee
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
greetings
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
add a comment |
You are using the wrong syntax:
this.getApplicationTokens().then(
(data) => {
this._tokens = <string>data; // note: turned into an arrow function and added the `this` keyword
});
note if you kept using function() ... syntax the this keyword will not point to the class instance but to the callee
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
greetings
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
add a comment |
You are using the wrong syntax:
this.getApplicationTokens().then(
(data) => {
this._tokens = <string>data; // note: turned into an arrow function and added the `this` keyword
});
note if you kept using function() ... syntax the this keyword will not point to the class instance but to the callee
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
greetings
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
You are using the wrong syntax:
this.getApplicationTokens().then(
(data) => {
this._tokens = <string>data; // note: turned into an arrow function and added the `this` keyword
});
note if you kept using function() ... syntax the this keyword will not point to the class instance but to the callee
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
greetings
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
answered Nov 13 '18 at 14:30
messerbillmesserbill
2,9411125
2,9411125
add a comment |
add a comment |
Properties of a class do not have a scope, they live as long as the object they belong to live and everything that can access the object can access all its properties too. However properties always have to be accessed on their object, e.g. something._tokens or this._tokens inside methods. Also you have to make sure that this is what you think it is, in your case you have to use an arrow function to access the correct this inside a callback:
this.getApplicationTokens().then( (data) => {
this._tokens = data as string;
});
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
Thanks. I have not learned much/anything about arrow functions! Also for the helpful link!
– Gary O. Stenstrom
Nov 13 '18 at 14:39
add a comment |
Properties of a class do not have a scope, they live as long as the object they belong to live and everything that can access the object can access all its properties too. However properties always have to be accessed on their object, e.g. something._tokens or this._tokens inside methods. Also you have to make sure that this is what you think it is, in your case you have to use an arrow function to access the correct this inside a callback:
this.getApplicationTokens().then( (data) => {
this._tokens = data as string;
});
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
Thanks. I have not learned much/anything about arrow functions! Also for the helpful link!
– Gary O. Stenstrom
Nov 13 '18 at 14:39
add a comment |
Properties of a class do not have a scope, they live as long as the object they belong to live and everything that can access the object can access all its properties too. However properties always have to be accessed on their object, e.g. something._tokens or this._tokens inside methods. Also you have to make sure that this is what you think it is, in your case you have to use an arrow function to access the correct this inside a callback:
this.getApplicationTokens().then( (data) => {
this._tokens = data as string;
});
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
Properties of a class do not have a scope, they live as long as the object they belong to live and everything that can access the object can access all its properties too. However properties always have to be accessed on their object, e.g. something._tokens or this._tokens inside methods. Also you have to make sure that this is what you think it is, in your case you have to use an arrow function to access the correct this inside a callback:
this.getApplicationTokens().then( (data) => {
this._tokens = data as string;
});
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
answered Nov 13 '18 at 14:31
Jonas WilmsJonas Wilms
56.1k42851
56.1k42851
Thanks. I have not learned much/anything about arrow functions! Also for the helpful link!
– Gary O. Stenstrom
Nov 13 '18 at 14:39
add a comment |
Thanks. I have not learned much/anything about arrow functions! Also for the helpful link!
– Gary O. Stenstrom
Nov 13 '18 at 14:39
Thanks. I have not learned much/anything about arrow functions! Also for the helpful link!
– Gary O. Stenstrom
Nov 13 '18 at 14:39
Thanks. I have not learned much/anything about arrow functions! Also for the helpful link!
– Gary O. Stenstrom
Nov 13 '18 at 14:39
add a comment |
I think you're just missing the this keyword from _tokens:
this._tokens = <string>data;
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
answered Nov 13 '18 at 14:30
KCM78KCM78
34
this is not enough, the OP also has to change the callback function into an arrow function, otherwisethiswill not point to the classes instance
– messerbill
Nov 13 '18 at 14:35
add a comment |
I think you're just missing the this keyword from _tokens:
this._tokens = <string>data;
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
answered Nov 13 '18 at 14:30
KCM78KCM78
34
this is not enough, the OP also has to change the callback function into an arrow function, otherwisethiswill not point to the classes instance
– messerbill
Nov 13 '18 at 14:35
add a comment |
I think you're just missing the this keyword from _tokens:
this._tokens = <string>data;
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
answered Nov 13 '18 at 14:30
KCM78KCM78
34
I think you're just missing the this keyword from _tokens:
this._tokens = <string>data;
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
answered Nov 13 '18 at 14:30
KCM78KCM78
34
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
edited Nov 13 '18 at 14:34
qiAlex
2,0261724
2,0261724
answered Nov 13 '18 at 14:30
KCM78KCM78
34
answered Nov 13 '18 at 14:30
KCM78KCM78
34
answered Nov 13 '18 at 14:30
KCM78KCM78
34
34
this is not enough, the OP also has to change the callback function into an arrow function, otherwisethiswill not point to the classes instance
– messerbill
Nov 13 '18 at 14:35
add a comment |
this is not enough, the OP also has to change the callback function into an arrow function, otherwisethiswill not point to the classes instance
– messerbill
Nov 13 '18 at 14:35
this is not enough, the OP also has to change the callback function into an arrow function, otherwise
this will not point to the classes instance– messerbill
Nov 13 '18 at 14:35
this is not enough, the OP also has to change the callback function into an arrow function, otherwise
this will not point to the classes instance– messerbill
Nov 13 '18 at 14:35
add a comment |
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1
There are several question about this error on Stack Overflow. Do any of those help you?
– Heretic Monkey
Nov 13 '18 at 14:32