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Gavin Kistner a écrit :
That's the internal model I'm seeing. Closures do not bind to values, but rather to variables that hold or reference values. Each usage of 'local' creates a new variable. "a = 30" has to figure out what 'a' is, and finds the recently-declared 'a' which the 'g' closure is also using. Modifying the value in the variable affects the closure as well. "local a = 30" doesn't look to see if another existing local 'a' exists; it just creates a brand new variable. This behavior only surprises me because it is different from how JavaScript's "var" keyword behaves.
Does this mean that: local t = '' repeat local r = math.random(1, 50) t = t .. " " .. r until (string.len(t) > 100) print(t) is less efficient than declaring the local r outside the loop? At least in terms of memory?This idiom is very frequent in (semi-)compiled languages (C++/Java...), relying on the compiler optimizations to put the variable declaration outside the loop, but it can be an overkill in Lua. Being old-fashioned and from a time where compilers weren't so good, I tends to put the declarations outside loops if I can...
Since there is no function declaration here, I suppose there is no closure, so I am unsure if your statements are still true here.
-- Philippe Lhoste -- (near) Paris -- France -- http://Phi.Lho.free.fr -- -- -- -- -- -- -- -- -- -- -- -- -- --