PARSEC expressions

Parsec expressions group represents the concept of parser combinator.

They provide a way to combine basic parsers in order to construct more complex parsers for specific rules. In this context, a parser is a function that takes a single string as input and produces a structured output, that indicates successful parsing or provide an error message if the parsing process fails.

Parsec expressions are divided into two groups: parsers and combinators.

Parsers can be seen as the fundamental units or building blocks. They are responsible for recognizing and processing specific patterns or elements within the input string.

Combinators are operators (higher order functions) that allow the combination and composition of parsers.

Every expression starts with !PARSE. prefix.