Mastering PHP Design Patterns

Magic numbers

Note how in the preceding example I always put my constant numeric variables in class constants, as opposed to directly putting them in the code itself:

  const minRate = 2.50; 
  const secondsInDay = 60 * 60 * 24; 
  const mileRate = 0.2; 

The reason I did this was to avoid an anti-pattern known as magic numbers or unnamed numerical constants. Using class constants makes code easier to read, understand, and maintain; and of course, under the PSR standards, they should be declared in uppercase, separated by underscores.