feat: 词条隐藏、降频 (#249) close #242

lua/cold_word_drop/string.lua

@@ -0,0 +1,40 @@
+-- wrap utf8.sub(str,head_index, tail_index)
+-- wrap string.split(str,sp,sp1)
+--      string.utf8_len = utf8.len
+--      string.utf8_offset= utf8.offset
+--      string.utf8_sub= utf8.sub
+function string.split( str, sp,sp1)
+  sp =type(sp) == "string"  and sp or " "    
+  if #sp == 0 then
+    sp= "([%z\1-\127\194-\244][\128-\191]*)"
+  elseif #sp == 1 then 
+    sp= "[^" ..  (sp=="%" and "%%" or sp) .. "]*"  
+  else 
+    sp1= sp1 or "^"
+    str=str:gsub(sp,sp1)
+    sp=  "[^".. sp1 .. "]*"
+  end 
+
+  local tab= {}
+  for v in str:gmatch(sp) do
+    table.insert(tab,v)
+  end 
+  return tab 
+end
+
+function utf8.gsub(str,si,ei)
+  local function index(ustr,i)
+    return i>=0 and ( ustr:utf8_offset(i) or ustr:len() +1 )
+    or ( ustr:utf8_offset(i) or 1 )
+  end
+
+  local u_si= index(str,si)
+  ei = ei or str:utf8_len()
+  ei = ei >=0 and ei +1 or ei
+  local u_ei= index(str, ei ) -1
+  return str:sub(u_si,u_ei)
+end
+string.utf8_len= utf8.len
+string.utf8_offset=utf8.offset
+string.utf8_sub= utf8.gsub
+return true