create/access dynamic growth list

[Kent Johnson]

sam wrote:
> Since each line of the configuration file need to be parsed into "key" 
> and "value" pairs, these pair of tokens need to be stored in another 
> list. Can I use the following operation to store these pair of tokens?
> eg.
> Assumed macro_hash["key"]="some key"
>     macro_hash["value"]="some value"
> then build a list that contains a list of macro_hash:
>    macro_list.append(macro)
> when treverse the macro_list, it would be similar to perl:
>    foreach macro (in macro_list)
>     key = macro["key"]
>     value = macro["value"]
> 

Why not just store the key, value pairs as actual keys and values of a map? Creating a list of maps 
seems a bit contorted here. Instead of
 >     macro_hash["key"]="some key"
 >     macro_hash["value"]="some value"

followed by creating a list of macro_hashes, just use
   macro_hash["some key"] = "some value"

You lose the order of values but gain much easier lookup.

Alternatively just create a list of (key, value) pairs with
   macro_list = []
   macro_list.append( ("some key", "some value") )

which preserves the order at the expense of easy random access.

Kent