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[REBOL] Re: Does REBOL cons?

From: tim-johnsons::web::com at: 15-Mar-2006 14:52

* Jeff Massung <> [060315 13:48]:
> My question was more fundamental: "Does REBOL use consing for its lists > internally?"
the lisp cons is *not* internal, it is produced by a C code that adds an item to a linked (I think) list. The rebol 'insert action value is produced by C code that resizes a contiguous block of memory with the value as the first item. I think that rebol lists are linked lists tho' and I *believe* that 'insert acts on them too. But take note of the return value (cons CAR CDR) returns new list. 'insert returns the insertion point. Here's a nother quick rebol console session:
>> test: [2 3 4]
== [2 3 4]
>> res: insert test 1
== [2 3 4]
>> res
== [2 3 4]
>> test
== [1 2 3 4]
>> help insert ;; see the underscored line
USAGE: INSERT series value /part range /only /dup count DESCRIPTION: Inserts a value into a series and returns the series after the insert. ---------------------------------------------------------------------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^ INSERT is an action value. ARGUMENTS: series -- Series at point to insert (Type: series port bitset) value -- The value to insert (Type: any-type) REFINEMENTS: /part -- Limits to a given length or position. range -- (Type: number series port) /only -- Inserts a series as a series. /dup -- Duplicates the insert a specified number of times. count -- (Type: number) :-) Watch them/thar return values, they will surprise you. Fortunately, you're familiar with lisp so you will be looking for return values from loops and conditionals. That's something else I hand to get used to. HTH tim -- Tim Johnson <>