WoW:USERAPI tinsertbeforeval

This page documents a <i>user-defined function</i> that you can copy and paste into your addon. Replace PREFIX with your addon or lib prefix to avoid conflicts between different versions of these functions.

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Table Helpers - by Mikk -

Miscellaneous table helper functions.

 tinsertbeforeval(tab, valBefore, val)

 boolRemoved = tremovebyval(tab, val)

 num = tcount(tab)

 tcopy(to, from)

Note that tinsertbeforeval and tremovebyval iterate over the table to find their targets; they can be quite slow compared to regular inserts/deletes.

Examples

 local tab = { "alice", "charles" }
 tinsertbeforeval(tab, "charles", "bob");
 → tab: "alice", "bob", "charles"
 tinsertbeforeval(tab, "alice", "zeta");
 → tab: "zeta", "alice", "bob", "charles"

 bool = tremovebyval(tab, "zeta");
 → bool = true
 bool = tremovebyval(tab, "zeta");
 → bool = false

 tab2["foo"]="bar";
 tab2["abc"]="xyz";
 myCount = tcount(tab2);
 → myCount = 2

 tcopy(tab2, tab);
 → tab2:  
   ["foo"]="bar", 
   ["abc"]="xyz", 
   [1]="alice", 
   [2]="bob", 
   [3]="charles"

Code

 -- tinsertbeforeval: insert a value before another value (given only values)
 --   assumes integer-indexed table, or "before" loses its meaning
 function <PREFIX>_tinsertbeforeval(tab, valBefore, val)
   for k,v in ipairs(tab) do
     if(v==valBefore) then
       table.insert(tab, k, val);
       return;
     end
   end
   -- print("insertbeforeval: Could not find \""..valBefore.."\". Appending last.");
   table.insert(tab, val);
 end
 
 -- tremovebyval: remove a table row given its value
 function <PREFIX>_tremovebyval(tab, val)
   for k,v in tab do
     if(v==val) then
       table.remove(tab, k);
       return true;
     end
   end
   return false;
 end
 
 -- tcount: count table members even if they're not indexed by numbers
 function <PREFIX>_tcount(tab)
   local n=0;
   for _ in pairs(tab) do
     n=n+1;
   end
   return n;
 end
 
 -- tcopy: recursively copy contents of one table to another
 function <PREFIX>_tcopy(to, from)   -- "to" must be a table (possibly empty)
   for k,v in pairs(from) do
     if(type(v)=="table") then
       to[k] = {}
       <PREFIX>_tcopy(to[k], v);
     else
       to[k] = v;
     end
   end
 end