2013/9/10 Antoine Pitrou email@example.com:
In http://bugs.python.org/issue18986 I proposed adding a new mapping type to the collections module.
The original use case is quite common in network programming and elsewhere (Eric Snow on the tracker mentioned an application with stock symbols). You want to have an associative container which matches keys case-insensitively but also preserves the original casing (e.g. for presentation). It is a commonly reimplemented container.
If it is commonly reimplemented, what is the most common name? :-)
The http.client and email.message modules convert headers to lower case, but keep the original case.
Do you know a use case where values need also to be transformed? If not, I prefer the transformdict name.
I only read "coerce" in old Python documentation, not in other languages. I prefer the more common and generic term "tranform".