[Chicken-janitors] #1445: Support parameterised hash table type declarations

[Chicken Trac]

#1445: Support parameterised hash table type declarations
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 Reporter:  evhan                 |                 Owner:
     Type:  enhancement           |                Status:  new
 Priority:  not urgent at all     |             Milestone:  someday
Component:  unknown               |               Version:  5.0
 Keywords:  scrutiniser, srfi-69  |  Estimated difficulty:
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 As suggested by megane on [https://lists.nongnu.org/archive/html/chicken-
 hackers/2018-02/msg00008.html chicken-hackers].

 Support specifying the types of hash table keys and values:

 {{{
 (define t (the (hash-table fixnum symbol) ...))

 (hash-table-ref t 'foo) ; warning "expected argument #2 of type `fixnum'
 but was given an argument of type `symbol'"

 (hash-table-ref t 42) ; result would be known to be a symbol
 }}}

 And so on.

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Ticket URL: <https://bugs.call-cc.org/ticket/1445>
CHICKEN Scheme <https://www.call-cc.org/>
CHICKEN Scheme is a compiler for the Scheme programming language.