Showing dictionary key value pairs on a screen [SOLVED]

[RicharDann]

For an inventory system I'm making for my game I need to use dictionaries and be able to show their contents in a screen, the dictionary seems to be working fine but when I try to show it's contents, Ren'Py throws me an error. Here's what I have been testing with:

Code: Select all

default a_dict = {'a':1,'b':2,'c':3}

screen test_dict(d):
    frame:
        vbox:
            for k in d.keys():
                text "[k] has value [d[k]]." # <-- I think the problem is here
                
label start:

    show screen test_dict(a_dict)

When I run the game, this error shows up (Only putting the relevant part here):

Code: Select all

I'm sorry, but an uncaught exception occurred.
  File "game/script.rpy", line 16, in execute
    text "[k] has value [d[k]]."
KeyError: u'k'

I imagine it's a conflict with the brackets inside the brackets needed to access the key's value. Is there another way I can show this value without using the []?

[philat]

You can't "double" interpolate with brackets -- in other words, [d[k]] is looking for the value of a_dict[k], which doesn't exist. Either use .format interpolation (which you can search for) or string concatenation (i.e., "[k] has value " + str(d[k])).

[RicharDann]

use .format interpolation (which you can search for) or string concatenation (i.e., "[k] has value " + str(d[k])).

Oh of course *facepalm* why didn't I think of that? str() works just fine, thanks!

[Remix]

You could also interpret the value within the for loop:

for key, value in d.iteritems():
.... text "[key] = [value]"

You will find though, with dictionary keys being unordered that it might be best to iterate a sorted list rather than leave it to chance as to which order they are output...

for key, value in sorted( d.items() ):
.... text "[key] = [value]"

[RicharDann]

You could also interpret the value within the for loop:

for key, value in d.iteritems():
.... text "[key] = [value]"

You will find though, with dictionary keys being unordered that it might be best to iterate a sorted list rather than leave it to chance as to which order they are output...

for key, value in sorted( d.items() ):
.... text "[key] = [value]"

Hey, that's an interesting approach too, and you're right I might need to sort the items in the future so I will be sure to keep your advice in mind, thank you both for your help!