I have an interface: object properties and methods… the error says that please help me to type correctly I already tried to make another type (keyof IView on string), but again i get error Answer You need to use a generic to make the param type match the value type:
Tag: types
Change passable prop to a function to simplify them
I have this code that contain props it’s took 3 line for only props I have assignment to change the props into a function to simplified them, so I can import them as a function and only take 1 line for props Answer You can use an object notation to pass the props where key and value are the same
TypeScript can’t assign an Object Type to Record
I’m learning TypeScript, and decided to try implement it in a small portion of my codebase to get the ball rolling. Specifically, what I’m refactoring now is related to a fixture “factory” for the purpose of generating fixtures for Jest tests. In addition to these factories, which spit…
Typescript custom type
If I have an interface in typescript like so How can I factor out my type for text with the pipes so I can use it multiple times as a type in my program? It seems like it should be simple but I’m not sure what the syntax is For clarity I would like to be able to use it
How to force a type in a variable : The property does not exist in the type ‘AllMatch | SingleMatch’ ts(2339)
I have an interface of this shape: And I need to access the value field of the SingleMatch interface on a variable. To do this I use the following code: In the buildMonoExpressionSingleMatch() function I can access my variable without error if I check before that the function is of the right type for index 0:…
Using union type as function parameter
I have a type defined like so: where FieldValue is a union of types: I have a variable object where I then declare the functions set by the above types: This produces an error where the values in the object are not of type FieldToAction, I kind of understand why since I am now constraining the parameter to be…
TypeScript: Is it possible to define a variadic function that accepts different types of arguments?
I want to write a generic function that accepts variable number of arguments that may have different types and returns a tuple based on those arguments. Here is an example in JavaScript: And in TypeScript I need to somehow convert the spread argument tuple to a resulting one: I’ve tried a naive approach…
Typescript – make one type equal to another but with its properties being optional
I have 2 types: In this example, CoreOptions is meant to have some, none, or all of the properties that Core has depending on the use case, but never to have a property that isn’t in Core. I am trying to systematically tie them together so that as things evolve and Core gets new properties, I only have …
JavaScript converting the string “constructor” to [Function: Object]
I’m building a parser for a simple interpreter in JavaScript. I have a preprocessor method that removes specific tokens from an input list of tokens produced by the tokenizer: Each token is an object like this, with both type and value being strings: Somewhere in this function, when tokens[i].value == &…
Typescript Pick optionnal unset variable
I’m trying to use the “pick” function of typescript to get all the possible values of my objects. My objects have optional attributes so they are not necessarily set and I also try to convert “type” attribut to a type with : but I think there is a better way to do it and I don…