standards and variants
The educational goal of this subchapter is to make the student aware that there are offcial versions of many programming languages, but that in practice there are a lot of variations (and that a programmer must be able to adapt to changes and variations).
Programming languages can meet official standards or come in variants and dialects.
standards and variants
Programming languages have traditionally been developed either by a single author or by a committee.
Typically after a new programming language is released, new features or modifications, called variants, start to pop-up. The different versions of a programming language are called dialects. Over time, the most popular of these variants become common place in all the major dialects.
If a programming language is popular enough, some international group or committee will create an official standard version of a programming language. The largest of these groups are ANSI (Ameican national Standards Institute) and ISO (International Orgnaization for Standardization).
While variants and dialects may offer very useful features, the use of the non-standard features will lock the program into a particular development environment or compiler and often will lock the program into a specific operating system or even hardware platform.
Use of official standaards allows for portability, which is the ability to move a program from one machine or operating system to another.
While variants were traditionally introduced in an attempt to improve a programming language, Microsoft started the practice of intentionally creating variants to lock developers into using Microsoft products. In some cases the Microsoft variants offered no new features, but merely chaanged from the established standard for the sake of being different. Microsoft lost a lawsuit with Sun Microsystems for purposely creating variants to Java in hopes of killing off Java in favor of Microsoft languages.
free music player coding example
Coding example: I am making heavily documented and explained open source code for a method to play music for free almost any song, no subscription fees, no download costs, no advertisements, all completely legal. This is done by building a front-end to YouTube (which checks the copyright permissions for you).
View music player in action: www.musicinpublic.com/.
Create your own copy from the original source code/ (presented for learning programming).
Because I no longer have the computer and software to make PDFs, the book is available as an HTML file, which you can convert into a PDF.
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