Minor improvements to Tigersay codebase.

tigersay.tig

@@ -6,9 +6,10 @@ let
     var false := 0
     var true  := 1
 
-    var INDENT := "        "
+    var INDENT   := "        "
-
+    var MAXWIDTH := 40
 
+    /* The cow is unused, and taken directly from the cowsay program. */
     var COW := "\
 \\\   ^__^                 \n\
 \ \\  (oo)\\_______        \n\
@@ -31,26 +32,56 @@ let
 \             ((__.-'((___..-'' \\__.'                "
 
 
-    /*************/
+    /***********/
-    /* Utilility */
+    /* Utility */
+
+    /* I/O */
 
     function getinput () : string =
       let var l := "" /* Full output  */
           var c := "" /* Current char */
       in while true do
             ( c := getchar()
-            ; if c = "" then break     /* Hit EOF */
+            ; if c = "" then  break     /* Hit EOF */
             ; l := concat(l, c) )
          ; l
       end
 
+    /* Number / Maths */
+
+    function max (a:int, b:int) : int =
+      if a > b then a else b
+
+    function modulo (num : int, mod : int) : int =
+      ( while num >= mod do
+              num := num - mod
+      ; num )
+
+    function exp (exponee : int, exponent : int) : int =
+      if exponent = 0 then  1
+                      else  exponee * exp(exponee, exponent - 1)
+
+    function get_digit (num : int, digit : int) : int =
+      modulo(num / exp(10, digit-1), 10)
+
+    function log10 (num : int) : int =
+      let var log10 := 1
+      in while num > 9 do
+           ( num := num/10
+           ; log10 := log10 + 1 )
+       ; log10
+      end
+
+
+    /* String manipulation */
+
     function concat3 (a:string, b:string, c:string) : string =
       concat(a, concat(b, c))
 
     function concat4 (a:string, b:string, c:string, d:string) : string =
       concat(a, concat(b, concat(c, d)))
 
-    function indentstring (text : string, before : string, after:string) : string =
+    function indent_string (text : string, before : string, after:string) : string =
       let var out := before
           var char := ""
       in for i := 0 to size(text) - 1 do
@@ -61,6 +92,52 @@ let
          concat(out, after)
       end
 
+    function is_whitespace (char:string) : int =
+      (char = "" | char = "\n" | char = " " | char = "\t")
+
+    function substring_absolute (text:string, i1:int, i2:int) : string =
+      /* Uses absolute coordinates to determine substring */
+      substring(text, i1, i2 - i1 + 1)
+
+    function count_substring_occurances (text:string, char:string) : int =
+      let var count := 0
+          var charwidth := size(char)
+      in for i := 0 to size(text) - charwidth do
+           if substring(text, i, charwidth) = char then
+               count := count + 1
+       ; count
+      end
+
+    function repeat_string (str:string, rep:int) : string =
+      let var out := ""
+      in for i := 1 to rep do
+            out := concat(out, str)
+       ; out
+      end
+
+    function digit_to_s (n:int) :string =
+      if 0 <= n & n <= 9
+      then chr(48 + n)
+      else "?"
+
+    function int_to_s (num : int) : string =
+      let var l := ""
+      in for i := 1 to log10(num) do
+           l := concat(digit_to_s(get_digit(num, i)), l)
+       ; l
+      end
+
+    function length_of_longest_line (text:string) : int =
+      let var longest := 0
+          var current := 0
+      in for i := 0 to size(text) - 1 do
+           if substring(text, i, 1) = "\n"
+           then ( longest := max(longest, current)
+                ; current := 0)
+           else current := current + 1
+       ; max(longest, current)
+      end
+
 
     /* Linked Lists */
 
@@ -84,13 +161,7 @@ let
       then  0
       else  1 + ll_length(ll.next)
 
-    var MAXWIDTH := 40
+    /**/
-
-    function is_whitespace (char:string) : int =
-      (char = "" | char = "\n" | char = " " | char = "\t")
-
-    function substringabs (text:string, i1:int, i2:int) : string =
-      substring(text, i1, i2 - i1 + 1)
 
     function split_words (text:string) : stringll =
       let var out := ll_new()
@@ -99,7 +170,7 @@ let
       in for i := 0 to size(text) - 1 do
           ( char := substring(text, i, 1)
           ; if is_whitespace(char) & prev_word_start_i <> -1
-            then ll_append(out, substringabs(text, prev_word_start_i, i - 1))
+            then ll_append(out, substring_absolute(text, prev_word_start_i, i - 1))
             else if not(is_whitespace(char)) & prev_word_start_i = -1
             then prev_word_start_i := i
           ; if is_whitespace(char) then  prev_word_start_i := -1
@@ -118,75 +189,37 @@ let
       in help(words, 0)
       end
 
-    function wrapstring (text:string, linewidth: int) : string =
+    function wrap_string (text:string, linewidth: int) : string =
       let var words := split_words(text)
           var splitstr := insert_whitespace_between_words(words, linewidth)
       in
-        if ll_length(splitstr) > 2 then
+        ll_to_s( if ll_length(splitstr) > 2
-          ll_to_s(splitstr.next.next.next)
+                 then splitstr.next.next.next
-        else
+                 else splitstr )
-          ll_to_s(splitstr)
       end
 
-    function max (a:int, b:int) : int =
-      if a > b then a else b
-
-    function longest_line_length (text:string) : int =
-      let var longest := 0
-          var current := 0
-      in for i := 0 to size(text) - 1 do
-           if substring(text, i, 1) = "\n"
-           then ( longest := max(longest, current)
-                ; current := 0)
-           else current := current + 1
-       ; max(longest, current)
-      end
-
-    function nr_char_in_str (text:string, char:string) : int =
-      let var count := 0
-          var charwidth := size(char)
-      in for i := 0 to size(text) - 1 do
-           if substring(text, i, charwidth) = char then count := count + 1
-       ; count
-      end
-
-    function rep_string (str:string, rep:int) : string =
-      let var out := ""
-      in for i := 1 to rep do  out := concat(out, str)
-       ; out
-      end
-
-    function digit_to_s (n:int) :string =
-      if 0 <= n & n <= 9
-      then chr(48 + n)
-      else "?"
-
-    function int_to_s (n:int) : string =
-      concat(digit_to_s(n/10), digit_to_s(n - n/10*10))
-
     /**************/
     /* Draw stuff */
 
-    function drawtextbubble (text:string) =
+    function draw_textbubble (text:string) =
       let
-          var textwidth  := longest_line_length(text)
+          var textwidth    := length_of_longest_line(text)
-          var textheight := nr_char_in_str(text, "\n") + 1
+          var textheight   := count_substring_occurances(text, "\n") + 1
-          var bubblewidth := textwidth + 4
+          var bubblewidth  := textwidth + 4
-          var after_text := concat3("\013\027[",int_to_s(bubblewidth-1),"C|")
+          var after_text   := concat3("\013\027[",int_to_s(bubblewidth-1),"C|")
-      in print(concat(" ", concat(rep_string("_", bubblewidth - 2), " \n")))
+      in print(concat3(" ", repeat_string("_", bubblewidth - 2), " \n"))
-       ; print(concat(indentstring(text, "| ", after_text), "\n"))
+       ; print(concat(indent_string(text, "| ", after_text), "\n"))
-       ; print(concat(" ", concat(rep_string("-", bubblewidth - 2), " \n")))
+       ; print(concat3(" ", repeat_string("-", bubblewidth - 2), " \n"))
       end
 
-    function drawtiger () = print(indentstring(TIGER, INDENT, ""))
+    function draw_tiger () = print(indent_string(TIGER, INDENT, ""))
 
     var text := getinput()
-    var wrappedtext := wrapstring(text, MAXWIDTH)
+    var wrappedtext := wrap_string(text, MAXWIDTH)
 in
-    drawtextbubble(wrappedtext);
+    draw_textbubble(wrappedtext);
-    drawtiger();
+    draw_tiger();
     print("\n");
     flush()
 end
 
-