Module:TemplateHelpers: Difference between revisions

← Older edit Newer edit →

@@ Line 116: / Line 116: @@
 function p.joinValues(values, delimiter)
      return NormalizationText.joinValues(values, delimiter)
+end
+-- Removes duplicate values from an array while preserving order
+-- @param t table The array to deduplicate
+-- @return table A new array with duplicates removed
+function p.removeDuplicates(t)
+    -- Type checking
+    if type(t) ~= 'table' then
+        return {}
+    end
+    -- Helper function to check if a value is NaN
+    local function isNan(v)
+        return type(v) == 'number' and tostring(v) == '-nan'
+    end
+    -- Pre-allocate result table (maximum possible size is #t)
+    local ret, exists = {}, {}
+    -- Process each value, preserving order
+    for i, v in ipairs(t) do
+        if isNan(v) then
+            -- NaNs can't be table keys, and they are also unique
+            ret[#ret + 1] = v
+        else
+            if not exists[v] then
+                ret[#ret + 1] = v
+                exists[v] = true
+            end
+        end
+    end
+    return ret
 end