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Modern Front-End Development for Rails, 2nd Edition
book

Modern Front-End Development for Rails, 2nd Edition

by Noel Rappin
September 2022
Intermediate to advanced content levelIntermediate to advanced
410 pages
10h 7m
English
Pragmatic Bookshelf
Content preview from Modern Front-End Development for Rails, 2nd Edition

Adding Type Annotations to Functions

Functions also get to participate in the static-typing fun. The parameters and return values can have type annotations, and the function as a whole has its own static type.

Annotating Function Parameters

TypeScript function parameters can have type annotations, with a similar syntax to what we’ve seen for variable declarations. The annotations work whether the function is a named function, an anonymous function, or a method of a class. All three of these examples have the same typing:

 function priceOfTicket(row: number, accessType: string) : number { }
 
 let priceOfTicket = function(row: number, accessType: string) : number { }
 
 class Ticket {
  priceOfTicket(row: number, accessType: string) : number ...
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Publisher Resources

ISBN: 9781680509977Errata Page