Another update from ingydotnet^djgoku

Task/Binary-strings/Forth/binary-strings-2.fth

@@ -1,6 +1,125 @@
-: empty? ( str len -- ? ) nip 0= ;
-: +c ( c str len -- ) + c! ;
-: replace-bytes ( from to str len -- )
-  bounds do
-    over i c@ = if dup i c! then
-  loop 2drop ;
+\ Rosetta Code Binary String tasks Console Tests
+
+\ 1. String creation and destruction (when needed and if there's no garbage collection or similar mechanism)
+
+\ RAW Forth can manually create a binary string with the C, operator.
+\ C, takes a byte off the stack and writes it into the next available memory address
+\ then increments the Forth internal memory pointer by 1 byte.
+\ 'binary_string'  drops it's address on the stack. Nothing more. (ie: pointer to the string)
+
+HEX ok
+    create binary_string   9 c,  1 c, 2 c, 3 c, 4 c, 5 c,
+                           0A c, 0B c, 0C c, 0FF c,        \ 1st byte is length
+ok
+
+\ test what we created using the DUMP utility
+
+ binary_string count dump
+ 25EC:7365  01 02 03 04 05 0A 0B 0C  FF 04 44 55 4D 50 00 20  ..........DUMP.
+ ok
+
+
+\ Alternatively we can create static string variables using our constructor
+    string: buffer1  ok
+    string: buffer2  ok
+
+DECIMAL  ok
+
+\ 2. String assignment
+
+\ create string constants with assignments(static, counted strings)  ok
+     create string1  ," Now is the time for all good men to come to the aid"
+     create string2  ," Right now!"  ok
+
+\ assign text to string variables with syntacic sugar
+     buffer1 =" This text will go into the memory allocated for buffer1"  ok
+     buffer2 =""  ok
+
+\ or use S" and PLACE
+     S" The rain in Spain..." buffer2 PLACE ok
+
+\ Test the assignments
+     string2 writestr Right now!
+ ok
+     string1 writestr Now is the time for all good men to come to the aid
+ ok
+     buffer1 writestr This text will go into the memory allocated for buffer1
+ ok
+     buffer2 writestr The rain in Spain...
+ ok
+
+
+\ destroy string contents. Fill string with zero
+     buffer1 clearstr  ok
+     buffer1 40 dump
+25EC:7370  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
+25EC:7380  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
+25EC:7390  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
+ ok
+
+\ 3. String comparison. ( the '.'  prints the top of the stack in these examples)
+     buffer1 =" ABCDEFG"  ok
+     buffer2 =" ABCDEFG"  ok
+
+     buffer1 buffer2 STR= .  ( should be -1, TRUE flag) -1  ok
+
+     string1 buffer1 str> .  ( should be  0) 0  ok
+     string1 buffer1 str< .  ( should be -1) -1  ok
+
+
+\ 4. String cloning and copying
+     string1 buffer1 COPYSTR  ok
+
+     string1 writestr Now is the time for all good men to come to the aid  ok
+     buffer1 writestr Now is the time for all good men to come to the aid  ok
+
+
+\ 5. Check if a string is empty
+     buffer1 len . 55  ok
+     buffer1 =""           \ assign null string  ok
+     buffer1 len . 0  ok
+
+
+
+\ 6. Append a byte to a string
+     buffer2 =" Append this"  ok
+     buffer2 writestr Append this
+ ok
+     char !  buffer2 APPEND-CHAR  ok
+     buffer2 writestr Append this!
+ ok
+hex  ok
+     0A buffer2 APPEND-CHAR     \ append a raw carriage return  ok
+     0D buffer2 APPEND-CHAR     \ append a raw line-feed  ok
+  ok
+     buffer2 writestr Append this!
+
+ ok
+\ we see the extra line before OK so Appending binary chars worked
+
+ decimal ok
+
+\ 7. Extract a substring from a string. Result placed in a temp buffer automagically
+
+     string1 writestr Now is the time for all good men to come to the aid ok
+
+     string1 5 11 substr writestr is the time ok
+
+
+\ 8. Replace every occurrence of a byte (or a string) in a string with another string
+\    BL is a system constant for "Blank" ie the space character (HEX 020)
+
+     buffer1 =" This*string*is*full*of*stars*"  ok
+  ok
+     BL  char *  buffer1 REPLACE-CHAR  ok
+     buffer1 writestr This string is full of stars
+ ok
+
+
+\ 9. Join strings
+     buffer1 =" James "  ok
+     buffer2 =" Alexander"  ok
+     buffer2 buffer1 CONCAT  ok
+  ok
+     buffer1 writestr James Alexander
+ ok