Disclaimer Every feature below (I think) can be realised in plain SQF functions, but it would be convenient for code, that heavily depends on new Hash Map Object, to write it "in engine".
Special keys
Many of these features are inspired by Lua metatables. While new HashMap Object have slightly different approach, we still can bring some of Lua metatables features to it.
"#*key"
Methods for controlling reads from and writes to hashmap like Lua metamethods:
- "#key" (Lua __index) - getting value of non-existing key:
- Passed parameters: ["_key"].
- getOrDefault returns default value only if this method returns nil.
- "#newkey" (Lua __newindex) - inserting a new key:
- Passed parameters: ["_key", "_value"].
- If this method is present, override the default insert behavior (new setraw command - more information below).
- If this method is present, call it even if the "sealed" flag is set or finalized.
- "#callkey" - calling non-existing method:
- Passed parameters: ["_key", "_params"].
New commands *raw
New commands: setRaw, getRaw, getOrDefaultRaw and callRaw - that work same as their regular counterparts, but don't call "#*key" methods and still follow "sealed" flag and finalization.
Like Lua rawget and rawset
Finalization of special keys only
This can be done through any of:
- New special flag "finalSpecial".
- or special method "#specialkey" that will override any write for special key.
Like Lua __metatable that allow disabling of modification metamethods.
Overriding operators
| Key | SQF | Parameters |
|---|---|---|
| "#add" | HASHMAP + ANYTHING | ["_rhs"] |
| "#radd" | ANYTHING + HASHMAP | ["_lhs"] |
| "#sub" | HASHMAP - ANYTHING | ["_rhs"] |
| "#rsub" | ANYTHING - HASHMAP | ["_lhs"] |
| "#mul" | HASHMAP * ANYTHING | ["_rhs"] |
| "#rmul" | ANYTHING * HASHMAP | ["_lhs"] |
| "#div" | HASHMAP / ANYTHING | ["_rhs"] |
| "#rdiv" | ANYTHING / HASHMAP | ["_lhs"] |
| "#mod" | HASHMAP % ANYTHING, HASHMAP mod ANYTHING | ["_rhs"] |
| "#rmod" | ANYTHING % HASHMAP, ANYTHING mod HASHMAP | ["_lhs"] |
| "#pow" | HASHMAP ^ ANYTHING | ["_rhs"] |
| "#rpow" | ANYTHING ^ HASHMAP | ["_lhs"] |
| "#eq" | HASHMAP == HASHMAP (Same for: isEqualTo, in, find and etc.) | ["_other"] |
| "#ne" | HASHMAP != HASHMAP (Same for: isNotEqualTo) | ["_other"] |
| "#lt" | HASHMAP < HASHMAP | ["_rhs"] |
| "#le" | HASHMAP <= HASHMAP | ["_rhs"] |
| "#gt" | HASHMAP > HASHMAP | ["_rhs"] |
| "#ge" | HASHMAP >= HASHMAP | ["_rhs"] |
| "#neg" | -HASHMAP | [] |
| "#not" | !HASHMAP, not HASHMAP | [] |
| "#shiftr" | HASHMAP >> ANYTHING | ["_rhs"] |
| "#rshiftr" | ANYTHING >> HASHMAP | ["_lhs"] |
| "#select" | HASHMAP select ANYTHING, HASHMAP # ANYTHING | ["_rhs"] |
| "#count" | count HASHMAP | [] |
| "#forEach" | CODE forEach HASHMAP | ["_code"] |
| "#call" | call HASHMAP, ANYTHING call HASHMAP | like normal call |
For binary operators where both operands are hashmaps with defined apropriate special method prioritize method of left operand.
Type checking
Everything below allow to write code like:
params [["_value", false, [true, 0, HashMapType1, HashMapType2]]];
switch (typeName _value) do {
case (typeName true) : {...};
case (typeName 0) : {...};
case (typeName HashMapType1) : {...};
case (typeName HashMapType2) : {...};
};
if (_value isEqualType HashMapType1) then {...};
if (_value isEqualType HashMapType2) then {...};typeName HASHMAP
Change typeName to returns "#type" for hashmaps if it's defined:
typeName HashMap;
// Same as
if not ("#type" in HashMap) exitWith {"HASHMAP"};
HashMap get "#type";isEqualType*
For each variant of isEqualType*: if comparing two hashmaps with defined "#type" in rhs hashmap then they are equal by type when lhs hashmap is equal to rhs hashmap by reference or any of hashmap from lhs "#base" are equal by reference to rhs hashmap:
HashMap1 isEqualType HashMap2;
// Same as
if not ("#type" in HashMap2) exitWith {true};
if (HashMap1 isEqualRef HashMap2) exitWith {true};
HashMap1 getOrDefault ["#base", []] findIf {_x isEqualRef HashMap2} != -1;param*
For hashmaps in expectedDataTypes input values are compared by algorithm described above:
params [["_value", false, [true, 0, HashMapType1, HashMapType2]]];
Misc
createHashMap HASHMAP
Returns copy of hashmap object as simple hashmap without any special methods.
Additional: if finilization of special keys or entire hashmap is present then this must fail.