37 lines
916 B
Forth
37 lines
916 B
Forth
LISP provides a function, `defstruct`, which creates a data
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structure and functions for accessing various fields in it.
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This can be useful, so I'm doing something similar here.
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(defstruct book title author subject book-id )
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~~~
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{{
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:make-helper (nsq-) [ d:create , ] dip does ;
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:make-struct (ns-) d:create , [ here swap fetch allot ] does ;
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---reveal---
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:defstruct (sa-)
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&s:keep dip dup a:length
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[ n:dec swap
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[ 'ab 'aabab reorder
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'@ s:append [ fetch + fetch ] make-helper
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'! s:append [ fetch + store ] make-helper
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n:dec
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] a:for-each drop
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] sip swap make-struct ;
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}}
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~~~
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```
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'book { 'title 'author 'subject 'book-id } defstruct
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book 'A const
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'The_Hobbit s:keep &A title!
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'J.R.R._Tolkien s:keep &A author!
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'Fantasy s:keep &A subject!
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:info (a-)
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[ subject@ ] [ author@ ] [ title@ ] tri
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'%s_by_%s_is_a_%s_book. s:format s:put nl ;
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&A info
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```
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