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On Monday 18 April 2005 4:55 am, Gavin Wraith wrote:
> Unfortunately this breaks referential transparency - a bad idea.
> The usual remedy for string manipulation is never to concatenate
> strings, but instead to use "stringles" - lists whose components

a similar solution is to change the underlying language implementation to 
something more appropriate.  the STL includes a 'rope' template.  the idea is 
similar to your 'stringles': a tree of strings.  the main difference is that 
the language itself manages them.  also, it's possible to use ref-counted 
copy-on-write string leaves, so that this code:

a="big string"
b=a.."suffix"

would reuse the 'big string'

in fact, when i first read about Lua, i saw in the doc that "unlike C strings, 
Lua strings are appropriate for big texts", and i hoped that meant it used 
ropes... but later i saw it wasn't so.

on a related issue: in LTN9, there's the advice not to build big strings by 
accumulation, instead it uses a stack and merges it down in a binary 
algorithm.

i ask: what about building an array with table.insert() and get the final 
string with table.concat()?  isn't that faster/easier?  maybe LTN9 is too 
old?

-- 
Javier

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