testReturn(): void function testReturn(): ?string function testReturn(): ?string Sodium is now a core extension Sodium is now a core extension Password hashing with Argon2 Password hashing with Argon2
This principle is about subtyping and inheritance. inheritance. Derived classes must be substitutable for their Derived classes must be substitutable for their base classes. base classes.
FAT Interfaces. Many client-speci c interfaces are better than one Many client-speci c interfaces are better than one general-purpose interface. general-purpose interface.
} interface Testable { public function t } class Programmer implements Codeable, Te { public function code() { return 'coding'; } public function test() { return 'testing in localhost'; } }
You might manage to work as a programmer for You might manage to work as a programmer for many years without knowing about a single many years without knowing about a single pattern. pattern. They're a toolkit of tried and tested solutions to They're a toolkit of tried and tested solutions to common problems in software design. common problems in software design. It de nes a common language that you and your It de nes a common language that you and your teammates can use to communicate more teammates can use to communicate more e ciently. e ciently.
public function minus( $num1, $num2); public function mul( $num1, $num2); public function divide( $num1, $num2); } class GmpCalculator extends Calculator { // calculation logic implementation } class BcMathCalculator extends Calculator { // calculation logic implementation } class Calculator { // calculation logic }