First class

First class (or 1st class, Firstclass) generally implies a high level of service, importance or quality. Specific uses of the term include:

Arts and Entertainment

Comics

Film

Music

Television

Computing

Leisure

Sports

Travel

First-class citizen

In programming language design, a first-class citizen (also type, object, entity, or value) in a given programming language is an entity which supports all the operations generally available to other entities. These operations typically include being passed as an argument, returned from a function, and assigned to a variable.

History

The concept of first- and second- class objects was introduced by Christopher Strachey in the 1960s. He did not actually define the term strictly, but contrasted real numbers and procedures in ALGOL:

During the 1990s, Raphael Finkel proposed definitions of second and third class values, but these definitions have not been widely adopted.

Examples

The simplest scalar data types, such as integer and floating-point numbers, are nearly always first-class.

In many older languages, arrays and strings are not first-class: they cannot be assigned as objects or passed as parameters to a subroutine. For example, neither Fortran IV nor C supports array assignment, and when they are passed as parameters, only the position of their first element is actually passed—their size is lost. C appears to support assignment of array pointers, but in fact these are simply pointers to the array's first element, and again do not carry the array's size.

First class (aviation)

First class is a travel class on some airliners intended to be more luxurious than business class, premium economy, and economy class. On a passenger jetliner, first class usually refers to a limited number (rarely more than 20) of seats or cabins toward the front of the aircraft which have more space, comfort, service, and privacy. In general, first class is the highest class offered, although some airlines have introduced new classes above this. Propeller airliners often had first class in the rear, away from the noise of the rotating propeller.

Service

Overview

First-class seats vary from large reclining seats with more legroom and width than other classes to suites with a fully reclining seat, workstation and TV surrounded by privacy dividers. International first-class seats usually have between 147–239 cm (58–94 inches) of seat pitch and between 48–89 cm (19–35 inches) of width while domestic flights may have between 86–173 cm (34–68 inches) of pitch and between 46–56 cm (18–22 inches) in width. In fact this means there is less discomfort for taller people. Some airlines have first-class seats which allow passengers to let one guest sit for a short while face-to-face with the occupant of the cabin.