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| − | Let's say i have Float:{233.594378, 345.634256, 1234.756464} array and i need reindex it two times. Two example:
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| − | <pawn>if (array[0] > some_float_variable)
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| − | x = 1.2 + array[0]</pawn>
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| − | or
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| − | <pawn>y = array[1] * array[1]</pawn>
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| − | Would it be more efficient (in fact)?
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| − | <pawn>new Float:temp = array[0]
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| − | if (temp > some_float_variable)
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| − | x = 1.2 + temp</pawn>
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| − | or
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| − | <pawn>new Float:temp = array[1]
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| − | y = temp * temp</pawn>--[[User:VEN|VEN]] 08:32, 3 March 2006 (EST)
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| − | :The bottom two are more efficient. However, it only really matters if you're repeating this computation a lot. If this is a one-time computation it won't make a difference. -- [[User:BAILOPAN|BAILOPAN]] 18:25, 3 March 2006 (EST)
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| − | ----
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| − | Regarding [[User:NiLuJe|NiLuJe]]'s change of '\0' to 0: while they are both the same, keeping the syntax in terms of characters would probably be better for people to understand when dealing with strings, so I reverted the changes back.
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| − | :Perhaps it should be changed to '^0'... by default we don't use \ for a backtick. This is probably what he meant to correct. -- [[User:BAILOPAN|BAILOPAN]] 18:55, 1 March 2006 (EST)
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| − | ::Ah, indeed, fixing that now --[[User:CyberMind|cybermind]] 02:39, 2 March 2006 (EST)
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| − | ----
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| − | Is there evidence that when something is const it's faster? I think this might be to the contrary, as the compiler has to copy it into the heap first to ensure that it isn't modified. -- [[User:BAILOPAN|BAILOPAN]] 00:54, 1 February 2006 (EST)
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| − | :Whether or not const variables/arrays are copied to the heap depends on the situation:
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| − | :<tt>For a function that has an array argument with a default value, the compiler allocates space for
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| − | :the default array value on the heap. However, if the array argument (with a default value) is
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| − | :also const, the pawn compiler passes the default array directly (there is no need to make a copy
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| − | :on the heap here, as the function will not attempt to change the array argument and, thereby,
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| − | :overwrite the default value).
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| − | :The arguments of a function that has "variable arguments" (denoted with the ... operator, see
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| − | :the pawn booklet "The Language") are always passed by reference. For constants and expressions
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| − | :that are not lvalues, the compiler copies the values to a cell that is allocated from the heap,
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| − | :and it passes the address of the cell to the function.</tt>
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| − | :-Page 106 (PDF page 108) of "The Implentor's Guide"
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| − |
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| − | :<tt>Function <i>insert</i> copies in the other direction and it does not change its function argument item.
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| − | :In such a case, it is advised to mark the function argument as "const". This helps the pawn parser
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| − | :to both check for errors and to generate better (more compact, quicker) code.</tt>
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| − | :-Page 21 (PDF page 23) of "The Language Guide"
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| − | :--[[User:CyberMind|cybermind]] 01:24, 1 February 2006 (EST)
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| − | <br />
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| − | ::I see, thanks for the clarification. Twilight, I'd amend your part somewhat to mirror that. -- [[User:BAILOPAN|BAILOPAN]] 02:54, 1 February 2006 (EST)
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