Hello,

Sorry to bother you with something trivial, but I am having trouble translating a block of code I wrote in Python over to D. Everything else I've figured out so far. Could someone help me understand how to get this right?

Here's the python:

scene = scenes["title"]

while 1 == 1:
    next_choice = None
    paths = scene["paths"]
    description = scene["description"]
    lines = string.split("\n")

    for line in lines:
        if len(line > 55):
            w = textwrap.TextWrapper(width=45, break_long_words=False)
            line = '\n'.join(w.wrap(line))
        decription += line +"\n"
    print description



    #Shows the choices
    for i in range(0, len(paths)):
        path = paths[i]
        menu_item = i + 1
        print "\t", menu_item, path["phrase"]

    print "\t(0 Quit)"

    #Get user selection

    prompt = "Make a selection ( 0 - %i): \n" % len(paths)

    while next_choice == None:
        try:
            choice = raw_input(prompt)
            menu_selection = int(choice)

            if menu_selection == 0:
                next_choice = "quit"
            else:
                index = menu_selection - 1
                next_choice = paths[ index ]

        except(IndexError, ValueError):
                print choice, "is not a valid selection"

    if next_choice == "quit":
        print "Thanks for playing."
        sys.exit()
    else:
        scene = scenes[ next_choice["go_to"] ]
        print "You decided to:", next_choice["phrase"], "\n"
        if sys.platform == 'win32':
            os.system("cls")
        else:
            os.system("clear")

I've got the very last piece set up, using consoleD to use clearScreen(), but The rest I'm not sure how to translate. Sorry for my incompetence in advance.

I'm not really sure exactly what parts are the issue, but I'll point out what I can:

On 05/07/2015 11:24 PM, avarisclari wrote:
> Hello,
>
> Sorry to bother you with something trivial, but I am having trouble
> translating a block of code I wrote in Python over to D. Everything else
> I've figured out so far. Could someone help me understand how to get
> this right?
>
> Here's the python:
>
> scene = scenes["title"]

It looks like scenes is a dictionary that stores dictionaries of strings? If so, then in D, scenes would be declared like this:

string[string][string] scenes;

Then the above line would be:

auto scene = scenes["title"]

>
> while 1 == 1:

In D, while(true) is probably prefered, but that's just a matter of style. 1==1 will work too.

>      next_choice = None
>      paths = scene["paths"]
>      description = scene["description"]
>      lines = string.split("\n")
>

Phobos (D's standard library) has a split:
http://dlang.org/phobos/std_array.html#split

Also one specifically for splitting lines:
http://dlang.org/phobos/std_string.html#splitLines

They're easier to use than it looks:
auto lines = description.split("\n");

or better yet (also handles mac and win-style properly):
auto lines = description.splitLines();


>      for line in lines:

Standard foreach:

for(ref line; lines) {

>          if len(line > 55):
>              w = textwrap.TextWrapper(width=45, break_long_words=False)

Exists in Phobos:
http://dlang.org/phobos/std_string.html#wrap

I've never actually used it myself though.

>              line = '\n'.join(w.wrap(line))

Join is easy:
http://dlang.org/phobos/std_array.html#join

result = (whatever array or range you want to join).join("\n")

But really, I don't think you'll need this entire loop at all, though. I would just strip all the newlines and feed the result to Phobos's wrap(). Probably something like:

auto description =
	scene["description"].replace("\n", " ").wrap(45);

That should be all you need for the word wrapping.

>          decription += line +"\n"

D uses ~ to concatenate strings instead of +. In D, + is just for mathematical addition.

>      print description
>

writeln(description);

>
>
>      #Shows the choices
>      for i in range(0, len(paths)):

foreach(i; 0..paths.length) {

>          path = paths[i]
>          menu_item = i + 1
>          print "\t", menu_item, path["phrase"]

writeln("\t", menu_item, path["phrase"]);
>
>      print "\t(0 Quit)"
>
>      #Get user selection

// Get user selection

>
>      prompt = "Make a selection ( 0 - %i): \n" % len(paths)

This is in phobos's std.conv: http://dlang.org/phobos/std_conv.html

So, either:

auto prompt = "Make a selection ( 0 - " ~
	paths.length.to!string() ~ "): \n";

or:

auto prompt = text("Make a selection ( 0 - ",
	paths.length, ~ "): \n")

>
>      while next_choice == None:
>          try:
>              choice = raw_input(prompt)

The basic equivalent to raw_input would be readln():
http://dlang.org/phobos/std_stdio.html#readln

But, the library Scriptlike would make this super easy, thanks to a contributer:
https://github.com/Abscissa/scriptlike

Pardon the complete lack of styling in the docs (my fault):
http://semitwist.com/scriptlike/interact.html

So, it'd be:

import scriptlike.interact;
auto choice = userInput!int(prompt);

>              menu_selection = int(choice)
>
>              if menu_selection == 0:
>                  next_choice = "quit"
>              else:
>                  index = menu_selection - 1
>                  next_choice = paths[ index ]
>
>          except(IndexError, ValueError):
>                  print choice, "is not a valid selection"
>
>      if next_choice == "quit":
>          print "Thanks for playing."
>          sys.exit()

I forget the function to exist a program, but if this is in your main() function, then you can just:

return;

>      else:
>          scene = scenes[ next_choice["go_to"] ]
>          print "You decided to:", next_choice["phrase"], "\n"
>          if sys.platform == 'win32':
>              os.system("cls")
>          else:
>              os.system("clear")
>
> I've got the very last piece set up, using consoleD to use
> clearScreen(), but The rest I'm not sure how to translate. Sorry for my
> incompetence in advance.

On 05/08/2015 12:06 AM, Nick Sabalausky wrote:
> On 05/07/2015 11:24 PM, avarisclari wrote:
>>
>> scene = scenes["title"]
>
> It looks like scenes is a dictionary that stores dictionaries of
> strings? If so, then in D, scenes would be declared like this:
>
> string[string][string] scenes;
>
> Then the above line would be:
>
> auto scene = scenes["title"]
>

BTW, D calls them "Associative Arrays" or "AA", instead of "dictionary". I *think* "dictionary" is what Python calls them, but I could be wrong.

On Friday, 8 May 2015 at 04:08:03 UTC, Nick Sabalausky wrote:
> On 05/08/2015 12:06 AM, Nick Sabalausky wrote:
>> On 05/07/2015 11:24 PM, avarisclari wrote:
>>>
>>> scene = scenes["title"]
>>
>> It looks like scenes is a dictionary that stores dictionaries of
>> strings? If so, then in D, scenes would be declared like this:
>>
>> string[string][string] scenes;
>>
>> Then the above line would be:
>>
>> auto scene = scenes["title"]
>>
>
> BTW, D calls them "Associative Arrays" or "AA", instead of "dictionary". I *think* "dictionary" is what Python calls them, but I could be wrong.

Yup, thank you for the help.

"Moving from Python to D"

always a good idea ;-)

On Friday, 8 May 2015 at 14:13:43 UTC, Chris wrote:
> "Moving from Python to D"
>
> always a good idea ;-)

You might be interested in this:

http://wiki.dlang.org/Programming_in_D_for_Python_Programmers

http://d.readthedocs.org/en/latest/examples.html#plotting-with-matplotlib-python

On Fri, 2015-05-08 at 03:24 +0000, avarisclari via Digitalmars-d-learn wrote:
> Hello,
> 
> Sorry to bother you with something trivial, but I am having trouble translating a block of code I wrote in Python over to D. Everything else I've figured out so far. Could someone help me understand how to get this right?
> 
> Here's the python:

This is Python 2 not Python 3!

Do you have a definition for scenes so I can run the code. Are there any tests of any sort?

For me Step 1 is to make this Python 3 and much more idiomatic Python. Doing this will also make the route to a D implementation far more obvious.


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