Haskell has a large standard library. A portion of the standard library, called the Prelude, is included by default in all Haskell packages. Prelude includes many useful and commonly used functions, so it serves as a core part of the standard library. It includes functions such as + and * as well as several functions used on lists (like head, tail, take, and drop).
The notation for function application is a bit different from it is common in mathematics. These differences are highlighted by the table below:
Mathematics Haskell f(x) f xf(x,y) f x yf(g(x)) f (g x)f(x,g(y)) f x (g y)f(x)g(y) f x * g yExcerpt from: Graham Hutton. âProgramming in Haskellâ (2nd ed.).
When defining a new function, the names of the function and its arguments must begin with a lower-case letter, but can then be followed by zero or more letters (both lower- and upper-case), digits, underscores, and forward single quotes.
Excerpt from: Graham Hutton. âProgramming in Haskellâ (2nd ed.).
Within a script, each definition at the same level must begin in precisely the same column. This layout rule makes it possible to determine the grouping of definitions from their indentation.
Excerpt from: Graham Hutton. âProgramming in Haskellâ (2nd ed.).