Return to awk.sml CVS log

Up to [Research Unix] / researchv10no / cmd / sml / doc / examples / awk

Annotation of researchv10no/cmd/sml/doc/examples/awk/awk.sml, revision 1.1.1.1

1.1       root        1: (* awk.sml *)
                      2: 
                      3: signature AWK =
                      4: sig
                      5:   val makeInt : string -> int  (* translates a digit string into an int *)
                      6:   val awk : instream * (string list  -> unit) * (unit -> unit) -> unit
                      7: end
                      8: 
                      9: structure Awk : AWK =
                     10: struct
                     11: 
                     12:   val digit0 = ord "0"
                     13:   and digit9 = ord "9"
                     14:   exception MakeInt
                     15:   fun makeInt (s:string) : int =
                     16:       (* translates string s into an integer.
                     17:          Bug: doesn't deal with negative integers *)
                     18:       let val len = length s
                     19:          fun translate(i,n) =
                     20:              if i<len
                     21:              then let val c = ordof(s,i)
                     22:                    in if digit0 <= c andalso c <= digit9
                     23:                       then translate(i+1,10*n+c-digit0)
                     24:                       else raise MakeInt
                     25:                   end
                     26:              else n
                     27:        in translate(0,0)
                     28:       end
                     29: 
                     30:   exception END
                     31: 
                     32:   fun parseStream (instream) = 
                     33:       fn () => if end_of_stream instream
                     34:               then raise END
                     35:               else Lex2.words(input_line(instream))
                     36: 
                     37:   fun awk(instream,step,final) =
                     38:       let val lines = parseStream instream
                     39:          fun iter () = (step(lines()); iter())
                     40:        in iter() handle END => final()
                     41:       end
                     42: 
                     43: end
                     44: 
                     45: 

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.