Expression (computer science)

An expression in a programming language is a combination of one or more explicit values, constants, variables, operators, and functions that the programming language interprets (according to its particular rules of precedence and of association) and computes to produce ("to return", in a stateful environment) another value. This process, as for mathematical expressions, is called evaluation. The returned value can be of various types, such as numerical, string, and logical.

For example, 2+3 is an arithmetic and programming expression which evaluates to 5. A variable is an expression because it denotes a value in memory, so y+6 is an expression. An example of a relational expression is 4≠4, which evaluates to false.

In C and most C-derived languages, a call to a function with a void return type is a valid expression, of type void. Values of type void cannot be used, so the value of such an expression is always thrown away.

In many programming languages a function, and hence an expression containing a function, may have side effects. An expression with side effects does not normally have the property of referential transparency. In many languages (e.g. C++), expressions may be ended with a semicolon (;) to turn the expression into an expression statement. This asks the implementation to evaluate the expression for its side-effects only and to disregard the result of the expression (e.g. "x+1;") unless it is a part of an expression statement that induces side-effects (e.g. "y=x+1;" or "func1(func2());").

Programming

Programming may refer to:

See also

Programming (music)

Programming is a form of music production and performance using electronic devices, such as sequencers, to generate sounds of musical instruments. Programming is used in nearly all forms of electronic music and in most hip hop music since the 1990s. It is also frequently used in modern pop and rap rock music from various regions of the world, and sometimes in jazz and contemporary classical music. In the 21st century, programming has been incorporated into various styles of screamo and metalcore music known as crunkcore and electronicore respectively.

See also

Notes

External links

Computer programming

Computer programming (often shortened to programming) is a process that leads from an original formulation of a computing problem to executable computer programs. Programming involves activities such as analysis, developing understanding, generating algorithms, verification of requirements of algorithms including their correctness and resources consumption, and implementation (commonly referred to as coding) of algorithms in a target programming language. Source code is written in one or more programming languages. The purpose of programming is to find a sequence of instructions that will automate performing a specific task or solving a given problem. The process of programming thus often requires expertise in many different subjects, including knowledge of the application domain, specialized algorithms and formal logic.

Related tasks include testing, debugging, and maintaining the source code, implementation of the build system, and management of derived artifacts such as machine code of computer programs. These might be considered part of the programming process, but often the term software development is used for this larger process with the term programming, implementation, or coding reserved for the actual writing of source code. Software engineering combines engineering techniques with software development practices.

Expression

Expression may refer to:

Linguistics

Symbolic expression

Bodily expression

Expression (architecture)

Expression (Lat. expressio) in architecture implies a clear and authentic displaying of the character or personality of an individual (architect). The expression is often identified with the architectural movement of expressionism, whose main starting point and aim is to present and express what has been „seen“ or experienced in the inner eye of the mind, heart and soul, i.e. to express the subjective moods and feelings without referring to conventional and „objective” values, judgments and truths. The main problem in the critical analysis of the theoretical interpretations of the concept of expression in architecture, lies in the fact that the concept of expression is used in different ways in different fields of science and art. Regarding the concept of expression, the following interpretations can often be found:

Expression (song)

"Expression" is the lead single released from Salt-n-Pepa's third album, Blacks' Magic. The song was both written and produced by member Cheryl "Salt" James.

The song became the group's second single to reach the top 40 in the US, peaking at number 28 on the Billboard Hot 100 while also topping the Hot Rap Singles chart at number one, becoming their first song to do so. The single was certified gold by the RIAA on February 28, 1990 before reaching platinum status less than three months later on May 25.

Single track listing

A-Side

B-Side

Chart history

1992 Re-Release

"Expression" was re-released in 1992 as the first (and only) single from Salt n Pepa's remix album, Rapped in Remixes: The Greatest Hits Remixed. The song peaked at number 23 in Ireland and the United Kingdom, which is higher than the original 1989 release.