Wikipedia itself makes important efforts to avoid qualifying XSLT as either a programming language or a markup language. For example, XSLT is a Turing-complete language², but is based on XML which is a markup language. The difference with programming languages is not always obvious. Markup languages are not considered as programming languages¹. For example, HTML enables to specify that some part of the document is a title or some other part is a list, by comparison to a flat text document. The key feature of a scripting language is that it can orchestrate other programs, just like a script gives the cue to an actor to start his part.Ī markup language is a language which is used to represent structured data. There are other languages like Java which are seldom used to "mediate between programs", not because this is impossible but because they are not designed to make this easy. a language may be both "scripting" and "programming": Python is regularly used to "mediate between programs", and also to "transform data". Note that scripting languages are a subset of programming languages i.e. Going back to the user list metaphor, in a programming language you write how to traverse a table of records, extract from each record the "name" field, and return all of them to the requester. Examples of transforming data is to compute a sum out of a number of addends, or solving a system of differential equations from a set of conditions, or writing and reading from a tree-like structure in a consistent manner given a sequence of possibly simultaneous queries. It does so by creating CPU instructions that rewrite the input data into the output hopefully, the desired output.
Going back to the user list metaphor, in a scripting language you ask the database "give me all user names", then ask the web server "send this user list to this requester".Ī programming language is used to transform data. Other typical programs you interact with are database servers, or web servers. The program that you control most of the time in those languages is the interpreter of the language itself, which accomplishes general tasks for you.
This is specially true of shell scripting languages like bash, but if you reflect about it, also Python or Perl came from the need to accomplish tasks in UNIX without writing a program in C. Of course, there will be numerous exceptions and counterexamples, since this is just my opinion.Ī markup language is used to control the presentation of data, like "represent these user names as a bullet list or as a table".Ī scripting language is used to mediate between programs in order to generate data. Let me attempt to find a dividing line between these three types of language.
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