Add "[", "[[" indexing for dictionary objects

[koheiw]

Dictionary objects are not long a list of characters (or a list), so we need an extractor.

[kbenoit]

I don't understand this issue... example of what behaviour is needed?

[koheiw]

This is the current behaviour:

dict <- dictionary(list(country = c("united states", "mexico", "canada"), 
                        "law words" = c('law*', 'constitution'), 
                        freedom = c('free', "freedom", 'libertarian')))

print(dict)
print(dict[1]) # not a dictionary
dictionary(dict[1]) # does not work

but it should be

print(dict[1:2])

# Dictionary object with 5 key entries.
# - country:
#     - united states, mexico, canada
# - law words:
#     - law*, constitution

dictionary(dict[1:2])

# Dictionary object with 5 key entries.
# - country:
#     - united states, mexico, canada
# - law words:
#     - law*, constitution

[kbenoit]

OK, now I understand. Agree this is a very useful addition.