WoW:USERAPI EraseTable: Difference between revisions
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(Add note that hashes never shrink) |
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{{ | {{localuserfunc}} | ||
__NOTOC__ | __NOTOC__ | ||
Erases a table, often a good way to reduce garbage creation. Note that erasing a table | Erases a table, often a good way to reduce garbage creation. Note that erasing a table can be more expensive than letting the GC system reclaim it, so one might prefer simply reallocating a new empty table. Also note that a hash (as opposed to a 1..n integer-index) will NEVER SHRINK. Each key you ever used will use ~40 bytes and keep doing so until the table is destroyed. If you re-use the same keys this is obviously a nonissue. | ||
For more details on the inner workings of tables and when to reallocate vs when to erase, see [[Lua object memory sizes]] and it's [[Talk:Lua object memory sizes|talk page]]. | |||
local function EraseTable(t) | local function EraseTable(t) | ||
for i in pairs(t) do t[i] = nil end | for i in pairs(t) do t[i] = nil end | ||
end | end | ||
Revision as of 20:20, 11 January 2008
Erases a table, often a good way to reduce garbage creation. Note that erasing a table can be more expensive than letting the GC system reclaim it, so one might prefer simply reallocating a new empty table. Also note that a hash (as opposed to a 1..n integer-index) will NEVER SHRINK. Each key you ever used will use ~40 bytes and keep doing so until the table is destroyed. If you re-use the same keys this is obviously a nonissue.
For more details on the inner workings of tables and when to reallocate vs when to erase, see Lua object memory sizes and it's talk page.
local function EraseTable(t) for i in pairs(t) do t[i] = nil end end