(S)ML-97 Examples

[Basics] of SML.

 

Hello world:

print "hello world\n" (* SML hello world program, LA 11/4/2005 *)

use: ne> sml Standard ML of ... - use "hello.sml"; [opening hello.sml] hello world val it = () : unit val it = () : unit -<CTRL>d - ne>

 

cat:

open TextIO; (* i.e. the I/O library *) fun cat fileName = let fun f inS = if endOfStream inS then ( closeIn inS; print "\n" ) else ( print (inputN(inS, 1)); f inS ) in f(openIn fileName) end; (* e.g. *) cat "cat.sml"; (* Copy file to std output, L.A., 11/4/2005 *) (* Also see I/O, Ch 4, *) (* Ullman "Elements of ML Programming" 1998 *)

 

[Big Ints], more than 32- or 64-bits.

 

[High-Order Functions] accept functions as parameters and/or return functions as results.

 

[Parser] (recursive descent) for expressions.

 

[Lazy data types] are not standard in SML but they can be implemented in the language.

 

[Structures, signatures, functors], struct, sig.

 

[Continuations] can be used to implement non-standard control mechanisms.

 

[Fixed-point operator, `Y'], note that Y does not refer to itself within its body, nor does the local function Ggg; one could rewrite Y to consist of only anonymous functions. Also see [λ/Y].

 

[semantics.toy] direct denotational sematics of a toy imperative language expressed in SML-97

 

Further Reading:

[λ-calculus].