대화형 모드의 진법(radix) 변환 예제 with OCaml

다음은  대화형 모드(interactive mode)에서 진법 변환(radix conversion)하는 OCaml 소스 코드이다.

   주: 이 소스는 Python 용으로 만들어 둔 소스를 F# 언어로 바꾸고, 다시 이를 Ocaml
        언어로 바꾸느라 OCaml 언어의 명령형 언어 특징을 위주로 짜여져 있다.

메뉴는 주메뉴 Command: (S)et radix, (A)bout, (Q)uit or E(x)it
와 부메뉴 SubCommand: 'main()' to goto Main menu, 'exit()' or 'quit()' to exit
로 구성되어 있으며, 진법 변환의 핵심은 소스 코드에 자체 작성된 함수 atoi  와  itoa 의 사용이다.

         let value = atoi str srcRdx
         let str = itoa value destRdx

지원되는 진법은 2진법에서 36진법까지이다.

 

1. (*
2.  *  Filename: convertRadix.ml
3.  *            Convert radix in an interactive mode.
4.  *
5.  *  Execute: ocaml convertRadix.ml
6.  *
7.  *   Or
8.  *
9.  *  Compile: ocamlc -o convertRadix.exe convertRadix.ml
10.  *  Execute: convertRadix
11.  *
12.  *      Date:  2013. 1. 28.
13.  *    Author:  P. Kim   ( pkim _AT_ scripts.pe.kr )
14.  *)
16. open Printf;;
18. exception RuntimeError of string
19. exception ValueError of string
20. exception Exit
22. let println s =
23.     printf "%s\n" s ;;
25. let print s =
26.    printf "%s" s  ;;
28. let printUsage() =
29.     println "Usage: convertRadix" ;
30.     println "Convert radix in a interactive mode, where the maximum radix is 36." ;;
32. let printAbout() =
33.     println "    About: Convert radix in a interactive mode."  ;;
35. let printMainMenu() =
36.     println "  Command: (S)et radix, (A)bout, (Q)uit or E(x)it"  ;;
38. let printMainPrompt() =
39.     print "  Prompt> "  ;;
41. let printSubMenu srcRadix destRadix =
42.     println (sprintf "    Convert Radix_%d to Radix_%d\n" srcRadix destRadix )  ;
43.     println ("    SubCommand: 'main()' to goto Main menu, 'exit()' or 'quit()' to exit" )  ;;
45. let printSubPrompt() =
46.     print "    Input Value>> " ;;
48. let split_char sep str =
49.   let rec indices acc i =
50.     try
51.       let i = succ(String.index_from str i sep) in
52.       indices (i::acc) i
53.     with Not_found ->
54.       (String.length str + 1) :: acc
55.   in
56.   let is = indices [0] 0 in
57.   let rec aux acc = function
58.     | last::start::tl ->
59.         let w = String.sub str start (last-start-1) in
60.         aux (w::acc) (start::tl)
61.     | _ -> acc
62.   in
63.   aux [] is ;;
65. let sBASE36 = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"  ;;
67. let contains s1 s2 =
68.   try
69.     let len = String.length s2 in
70.     for i = 0 to (String.length s1) - len do
71.       if String.sub s1 i len = s2 then raise Exit
72.     done;
73.     false
74.   with Exit -> true ;;
76. let join list sep =
77.     let rec join' list acc =
78.         match list with
79.             | [] -> ""
80.             | [single] -> single
81.             | one::[two] ->
82.                         if acc = "" then one ^ sep ^ two
83.                                     else acc ^ one ^ sep ^ two
84.             | first::others -> join' others (acc ^ first ^ ", ")
85.                                         in
86.                                         join' list "" ;;
88. let str_reverse str =
89.     let len = String.length str in
90.     let res = String.create len in
91.     for i = 0 to pred len do
92.         let j = pred len - i in
93.         res.[i] <- str.[j]
94.     done;
95.     res ;;
98. let itoa num radix =
99.    let isNegative = ref false in
100.    let num1 = num + 0 in
101.    let numx = ref num1 in
103.    if num < 0 then begin
104.       isNegative := true ;
105.       numx := (-num)
106.    end ;
108.    let nnumx = !numx in
110.    let q1 = nnumx in
111.    let q = ref q1 in
112.    let r = ref 0 in
113.    let slen = ref 1 in
115.    while (!q >= radix) do
116.        r := !q mod radix ;
117.        q := !q / radix ;
118.        slen := !slen + 1
119.    done ;
121.    let sslen = !slen in
123.    let str = String.create sslen in
124.    let p1 = nnumx in
125.    let p = ref p1 in
127.    for i = 0 to sslen - 1 do
128.        r := !p mod radix ;
129.        p := !p / radix ;
130.        str.[i] <- sBASE36.[!r]
131.    done ;
133.    let str2 = str_reverse str in
134.    str2;;
136. let atoi s radix =
137.     let ret = ref 0 in
138.     let isNegative = ref false in
139.     let len = String.length s in
140.     let valx = ref 0 in
141.     let c1 = s.[0] in
142.     let c = ref c1 in
144.     if !c = '-' then
145.         isNegative := true
146.     else if (!c >= '0' && !c <= '9') then
147.         ret := (int_of_char !c) - (int_of_char '0')
148.     else if (!c >= 'A' && !c <= 'Z') then
149.         ret := (int_of_char !c) - (int_of_char 'A') + 10
150.     else if (!c >= 'a' && !c <= 'z') then
151.         ret := (int_of_char !c) - (int_of_char 'a') + 10 ;
152.     if (!ret >= radix) then 
153.         raise (ValueError (sprintf "Can not read \"%s\" (as radix %d): '%c' is invalid." s radix !c ) ) ;
155.     for i = 1 to len - 1 do
156.         c := s.[i] ;
157.         ret := (!ret)*radix  ;
158.         if (!c >= '0' && !c <= '9') then
159.             valx := int_of_char !c - int_of_char '0' 
160.         else if (!c >= 'A' && !c <= 'Z') then
161.             valx := int_of_char !c - int_of_char 'A' + 10
162.         else if (!c >= 'a' && !c <= 'z') then
163.             valx := int_of_char !c - int_of_char 'a' + 10 ;
164.         if (!valx >= radix) then 
165.             raise (ValueError (sprintf "Can not read \"%s\" (as radix %d): '%c' is invalid." s radix !c ) ) ;
166.         ret := (!ret) + (!valx)
167.     done;
169.     if (!isNegative) then
170.         ret := (-(!ret) ) ;
172.     !ret ;;
175. let convertRadix s srcRdx destRdx =
176.     let valx = (atoi s srcRdx) in
177.     let ret = (itoa valx destRdx) in
178.     let ret2 = String.uppercase ret in
179.     ret2 ;;
182. let doConvert srcRadix destRadix =
183.     println "" ;
185.     printSubMenu srcRadix  destRadix ;
186.     let stop_flag = ref false in
187.     try
188.         while not (!stop_flag) do
189.             printSubPrompt() ;
190.             let tt = read_line() in
191.             let cmd = ref tt in
193.             while (String.length !cmd) = 0 do
194.                 let tt2 = read_line() in
195.                 cmd := tt2
196.             done;
198.             if "main()" = !cmd then begin
199.                 stop_flag := true ;
200.                 raise ( RuntimeError "" )
201.             end
202.             else if "exit()" = !cmd || "quit()" = !cmd then begin
203.                 exit 0
204.             end ;
206.             try 
207.                 let srcStr = !cmd in
208.                 let destStr = (convertRadix srcStr srcRadix destRadix) in
209.                 println (sprintf "        ( %s )_%d   --->   ( %s )_%d" srcStr srcRadix destStr destRadix ) ;
210.                 println ""
211.             with ValueError ex -> println (sprintf "    Error caused by: %s\n"  ex)
212.         done
213.     with RuntimeError ex -> println (sprintf " %s     "  ex);
214.     println "" ;;
217. let doStart() =
218.     let onlyOnce = ref true in
220.     try
221.         while true do
222.             print "" ;
223.             if (!onlyOnce) then begin
224.                 println "  The supported maximum radix is 36." ;
225.                 onlyOnce := false
226.             end ;
228.             printMainMenu() ;
229.             printMainPrompt() ;
231.             let tcmds = read_line() in
232.             let cmds = ref tcmds in
233.             while (String.length !cmds) = 0 do
234.                 let tt = read_line() in
235.                 cmds := tt
236.             done;
238.             let cmd = !cmds.[0] in
239.             if (contains  "qQxX" (sprintf "%c" cmd)) && (String.length !cmds) = 1 then begin
240.                 exit 0
241.             end
242.             else if (contains  "aA" (sprintf "%c" cmd)) && (String.length !cmds) = 1 then begin
243.                 printAbout()
244.             end
245.             else if (contains  "sS" (sprintf "%c" cmd)) && (String.length !cmds) = 1 then begin
246.                 print "  Input the source and target radices (say, 16 2): "  ;
247.                 let tt = read_line() in
248.                 let line = ref tt in
249.                 let ta = (split_char ' ' !line) in
250.                 let st = ref ta in
252.                 while (List.length !st) < 2 do
253.                     print "  Input the source and target radices (say, 16 2): "  ;
254.                     let tt2 = read_line() in
255.                     let ta2 = (split_char ' ' tt2) in
256.                     st := ta2
257.                 done;
259.                 let st2 = Array.of_list !st in
260.                 let srcRadix = int_of_string (st2.(0)) in
261.                 let destRadix = int_of_string (st2.(1)) in
262.                 doConvert srcRadix destRadix
263.             end ;
264.             print ""
265.        done 
266.     with RuntimeError ex -> println (sprintf "%s Error found!!" ex);;
269. (* Begin here *)
270. let main() =
271.     let cmdArgs = Sys.argv in
272.     if (Array.length cmdArgs > 1) && ("-h" = cmdArgs.(1)) then begin
273.         printUsage() ;
274.         exit 1
275.     end
276.     else begin
277.         doStart()
278.     end ;;
280. main();;
     

컴파일> ocamlc -o convertRadix.exe convertRadix.fs

실행> convertRadix

  The supported maximum radix is 36.
  Command: (S)et radix, (A)bout, (Q)uit or E(x)it
  Prompt> s
  Input the source and target radices (say, 16 2): 10 8

    Convert Radix_10 to Radix_8

    SubCommand: 'main()' to goto Main menu, 'exit()' or 'quit()' to exit
    Input Value>> 200
        ( 200 )_10   --->   ( 310 )_8

    Input Value>> main()

  Command: (S)et radix, (A)bout, (Q)uit or E(x)it
  Prompt> S
  Input the source and target radices (say, 16 2): 8 10

    Convert Radix_8 to Radix_10

    SubCommand: 'main()' to goto Main menu, 'exit()' or 'quit()' to exit
    Input Value>> 2666
        ( 2666 )_8   --->   ( 1462 )_10

    Input Value>> main()

  Command: (S)et radix, (A)bout, (Q)uit or E(x)it
  Prompt> x