27 Nov
2004
27 Nov
'04
4:42 a.m.
On 27 Nov 2004, at 00:59, Benjamin Franksen wrote:
I finally understood that George Russell's Library is not really about global variables. Rather it is about what I want to call 'execution contexts', which are -- as Marcin Kowalczyk observed -- a restricted form of dynamically scoped variables.
yes. [snip]
type XIO a = StateT Context IO a
...which, amusingly, brings us almost full circle to the message which sparked off this particular iteration of the Great Global Variables Debate: http://groups.google.com/groups?selm=fa.hvrd8p7.nmg2r7%40ifi.uio.no ..which uses StateT Env IO Although your work is rather more complete than what I sketch in that message. A problem is the ability to pass callbacks to external libraries... Jules