On Monday, 30 September 2013 at 23:27:48 UTC, bearophile wrote:
Inspired by a talk by Eden in the StrangeLoop 2013 conference,
I'd like to create a new small Rosettacode Task. Perhaps
someone here is able to review this task description a little,
or even to implement the D solution:
- - - - - - -TASK DESCRIPTION START- - - - - - - - -
Task Title: ASCII art diagram converter
Given the RFC 1035 message diagram from Section 4.1.1 (Header
section format) as a string:
http://www.ietf.org/rfc/rfc1035.txt
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ID |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|QR| Opcode |AA|TC|RD|RA| Z | RCODE |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| QDCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ANCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| NSCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ARCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Where:
ID is 16 bits
QR = Query (0) or Response (1)
Opcode = Four bits defining kine of query:
0: a standard query (QUERY)
1: an inverse query (IQUERY)
2: a server status request (STATUS)
3-15: reserved for future use
AA = Authoritative Answer bit
TC = Truncation bit
RD = Recursion Desired bit
RA = Recursion Available bit
Z = Reserved
RCODE = Response code
QC = Question Count
ANC = Answer Count
AUC = Authority Count
ADC = Additional Count</pre>
Write a function, member function, class or template that
accepts a similar multi-line string as input to define a data
structure or something else able to decode or store a header
with that specified bit structure.
If your language has macros, introspection, code generation, or
powerful enough templates, then accept such string at
compile-time to define the header data structure statically.
Such "Header" function or template should accept a table with
8, 16, 32, 64 columns and any number of rows. The only allowed
symbols to define the table are + - | (plus, minus, pipe), and
whitespace. Lines of the input string composed just of
whitespace should be ignored. Leading and trailing whitespace
in the input string should be ignored, as well as before and
after each table row. The box for each bit of the diagram takes
four chars "+--+". The code should perform a little of
validation of the input string, but for brevity a full
validation is not required.
- - - - - - -TASK DESCRIPTION END- - - - - - - - -
I think such ASCII art inside the source code is easy to read,
so in theory the D entry could be useful for more than just a
Rosettacode Task.
The usage syntax of the D entry:
alias H1 = BitfieldsTable!"
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ID |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|QR| Opcode |AA|TC|RD|RA| Z | RCODE |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| QDCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ANCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| NSCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| ARCOUNT |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+";
Bye,
bearophile
Nice idea! :)
I assume 1 column corresponds to 1 bit. This should probably be
mentioned explicitly in the task description.
