ℙ𝕖𝕡 🙴 ℕ𝕠𝕞

That is the last of a long series of straws. Groucho Marx, when the audience rushed outside to look at a donkey.

glossary for parsing terms

• pattern A very general term which is at the heart of how human beings understand the world. Formal languages specify patterns in one-dimensional alphabets of symbols; they determine if a particular sequence of symbols is included in a given language or not.
• formal language A set of sequences of symbols (letters) arranged in a single line. For example (aa, ab, ba) is a language with symbols “a” and “b”.
• markdown a minimalistic way to specify the structure/appearance of a plain-text document.
• virtual machine a logic machine which is implemented in software but not in hardware (silicon logic circuits).
• lex/parse 2 phases often used during compilation/transformation/translation
• recogniser A piece of software that determines whether a given input has a correct format for a given language or data format. The recogniser does not transform the input in any way, it simply returns true or false.
• bnf, backus-naur form A way to specify the structure of a context-free language. This is called the “grammar” of the language.
• context-free language A simple type of (formal/mathematical) language which has often formed the basis for computer languages. A context-free language is more complex than a “regular” language but (much) simpler than human language
• regular language A very simple type of (formal) language which is familiar to programmers from “regular expression” patterns. In general, a regular language cannot express “nested” structures (that is: text which is contained by other text delimiters). These are the patterns that sed and grep and see.
• natural language, human language These languages involve grammars in which there is an interdependence between semantics and grammatical structure. For this reason no good algorithms have yet been developed for the translation of human language (despite corporate hype and publicity).