Swift Language Style Conventions Fluent Usage
Example
Using natural language
Functions calls should be close to natural English language.Example:
list.insert(element, at: index)
instead of
list.insert(element, position: index)
Naming Factory Methods
Factory methods should begin with the prefix `make`.Example:
factory.makeObject()
Naming Parameters in Initializers and Factory Methods
The name of the first argument should not be involved in naming a factory method or initializer.Example:
factory.makeObject(key: value)
Instead of:
factory.makeObject(havingProperty: value)
Naming according to side effects
- Functions with side effects (mutating functions) should be named using verbs or nouns prefixed with
form-. - Functions without side effects (nonmutating functions) should be named using nouns or verbs with the suffix
-ingor-ed.
print(value)
array.sort() // in place sorting
list.add(value) // mutates list
set.formUnion(anotherSet) // set is now the union of set and anotherSet
Nonmutating functions:
let sortedArray = array.sorted() // out of place sorting
let union = set.union(anotherSet) // union is now the union of set and another set
Boolean functions or variables
Statements involving booleans should read as assertions.Example:
set.isEmpty
line.intersects(anotherLine)
Naming Protocols
- Protocols describing what something is should be named using nouns.
- Protocols describing capabilities should have
-able,-ibleor-ingas suffix.
Collection // describes that something is a collection
ProgressReporting // describes that something has the capability of reporting progress
Equatable // describes that something has the capability of being equal to something
Types and Properties
Types, variables and properties should read as nouns.Example:
let factory = ...
let list = [1, 2, 3, 4]
