2016 Update

Task/String-prepend/00DESCRIPTION

@@ -1,9 +1,17 @@
- {{basic data operation}}
-[[Category:String manipulation]] [[Category: String manipulation]] [[Category:Simple]]
+{{basic data operation}}
+[[Category:String manipulation]]
+[[Category: String manipulation]]
+[[Category:Simple]]
 {{omit from|bc|No string operations in bc}}
 {{omit from|dc|No string operations in dc}}
+
+;Task:
 Create a string variable equal to any text value.
+
 Prepend the string variable with another string literal.
+
 If your language supports any idiomatic ways to do this without referring to the variable twice in one expression, include such solutions.
 
+
 To illustrate the operation, show the content of the variable.
+<br><br>

Task/String-prepend/Ada/string-prepend.ada

@@ -0,0 +1,8 @@
+with Ada.Text_IO; with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;
+
+procedure Prepend_String is
+   S: Unbounded_String := To_Unbounded_String("World!");
+begin
+   S := "Hello " & S;-- this is the operation to prepend "Hello " to S.
+   Ada.Text_IO.Put_Line(To_String(S));
+end Prepend_String;

Task/String-prepend/COBOL/string-prepend-1.cobol

@@ -0,0 +1,25 @@
+       identification division.
+       program-id. prepend.
+       data division.
+       working-storage section.
+       1 str pic x(30) value "World!".
+       1 binary.
+        2 len pic 9(4) value 0.
+        2 scratch pic 9(4) value 0.
+       procedure division.
+       begin.
+           perform rev-sub-str
+           move function reverse ("Hello ") to str (len + 1:)
+           perform rev-sub-str
+           display str
+           stop run
+           .
+
+       rev-sub-str.
+           move 0 to len scratch
+           inspect function reverse (str)
+           tallying scratch for leading spaces
+               len for characters after space
+           move function reverse (str (1:len)) to str
+           .
+       end program prepend.

Task/String-prepend/Forth/string-prepend.fth

@@ -0,0 +1,19 @@
+\ the following functions are commonly native to a Forth system. Shown for completeness
+
+: C+!     ( n addr -- ) dup c@ rot + swap c! ;             \ primitive: increment a byte at addr by n
+
+: +PLACE  ( addr1 length addr2 -- )                        \ Append addr1 length to addr2
+          2dup 2>r  count + swap move 2r> c+! ;
+
+: PLACE   ( addr1 len addr2 -- )                           \ addr1 and length, placed at addr2 as counted string
+          2dup 2>r  1+  swap  move  2r> c! ;
+
+\ Example begins here
+: PREPEND ( addr len addr2 -- addr2)
+           >R                                              \ push addr2 to return stack
+           PAD PLACE                                       \ place the 1st string in PAD
+           R@  count PAD +PLACE                            \ append PAD with addr2 string
+           PAD count R@   PLACE                            \ move the whole thing back into addr2
+           R> ;                                            \ leave a copy of addr2 on the data stack
+
+: writeln ( addr -- ) cr count type ;                      \ syntax sugar for testing

Task/String-prepend/Fortran/string-prepend-1.f

@@ -0,0 +1,15 @@
+      INTEGER*4 I,TEXT(66)
+      DATA TEXT(1),TEXT(2),TEXT(3)/"Wo","rl","d!"/
+
+      WRITE (6,1) (TEXT(I), I = 1,3)
+    1 FORMAT ("Hello ",66A2)
+
+      DO 2 I = 1,3
+    2   TEXT(I + 3) = TEXT(I)
+      TEXT(1) = "He"
+      TEXT(2) = "ll"
+      TEXT(3) = "o "
+
+      WRITE (6,3) (TEXT(I), I = 1,6)
+    3 FORMAT (66A2)
+      END

Task/String-prepend/Fortran/string-prepend-2.f

@@ -0,0 +1,5 @@
+      CHARACTER*66 TEXT
+      TEXT = "World!"
+      TEXT = "Hello "//TEXT
+      WRITE (6,*) TEXT
+      END

Task/String-prepend/Maple/string-prepend.maple

@@ -0,0 +1,4 @@
+l := " World";
+m := cat("Hello", l);
+n := "Hello"||l;
+o := `||`("Hello", l);

Task/String-prepend/PlainTeX/string-prepend-1.tex

@@ -0,0 +1,11 @@
+\def\prepend#1#2{% #1=string  #2=macro containing a string
+	\def\tempstring{#1}%
+	\expandafter\expandafter\expandafter
+	\def\expandafter\expandafter\expandafter
+	#2\expandafter\expandafter\expandafter
+	{\expandafter\tempstring#2}%
+}
+\def\mystring{world!}
+\prepend{Hello }\mystring
+Result : \mystring
+\bye

Task/String-prepend/PlainTeX/string-prepend-2.tex

@@ -0,0 +1,7 @@
+\def\prepend#1#2{% #1=string  #2=macro containing a string
+	\edef#2{\unexpanded{#1}\unexpanded\expandafter{#2}}%
+}
+\def\mystring{world!}
+\prepend{Hello }\mystring
+Result : \mystring
+\bye

Task/String-prepend/SNOBOL4/string-prepend.sno

@@ -0,0 +1,3 @@
+    s = ', World!'
+    OUTPUT = s = 'Hello' s
+END