[
Home
]
[ Index:
by date
|
by threads
]
[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
| Date: | -- (:) |
| From: | Pierre Weis <Pierre.Weis@i...> |
| Subject: | Re: Stdlib regularity |
> Yes! Yes! I always begin my Caml code by writing iota, and I wish it
> were included in the standard library. It's silly simple, and imprescindible.
>
> let iota n =
> let rec aux l n =
> if n > 0 then aux (n::l) (n-1) else l
> in aux [] n
We may reuse this ``prelude'' code that slightly generalizes iota (named
range in this version of the standard library):
(*\
\subsection{Lists of consecutive integers}
\index{Lists of consecutive integers}
\begin{caml_primitive}
interval
range
\end{caml_primitive}
\begin{itemize}
\item \verb"interval n m" returns the list of all integers in
increasing order, from \verb"n" to \verb"m".
\item \verb"range n" gives the first n integers.
\end{itemize}
\*)
let interval n m =
let rec loop l m =
if n > m then l else loop (m :: l) (pred m) in
loop [] m;;
let range = interval 1;;
Pierre Weis
INRIA, Projet Cristal, Pierre.Weis@inria.fr, http://cristal.inria.fr/~weis/