Using Lua Tables

[jussij]

Using the table feature of Lua it is easy to write a macro that takes a user input string and maps this input to a second string.

For example consider the following mapping.txt text file which maps a key word to a string value:

Code: Select all

return {
  -- Key      Value
  ["for"] = "for (int i = 0; i < 100; ++ 1)\n{\n}",
  ["do"]  = "do\n{\n}\nwhile(i < 0);",
  ["if"]  = "if ()\n{\n}",
}

The following macro will ask the user for a key input, load the above mapping file into an Lua table, search the table for the key provided and insert the value found into the currently writable document:

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function table_list(key_values)
  list = ""

  -- build up a list of the keys in the table
  for key, value in key_values do
    list = list .. key .. "\n"
  end

  return list
end

function key_macro()
  -- macro only works for documents
  local document = is_document()

  -- macro only works for read/write documents.
  local locked = is_read_only()

  if (locked == 1) or (document == 0) then
    message("This macro can only be run with a writable document file.")
    beep()
    return
  end

  -- the default key value
  local nill = ""

  -- ask for a user for a key value
  local key_value = user_input("Key Value:", nill)

  local result = string.len(key_value)

  if result > 0 then
    -- load the key mapping
    key_values = dofile("mapping.txt")

    -- use the key to look for the result
    result = key_values[key_value]

    -- see if anything was found
    if result ~= nil then
      screen_update_disable()

      -- print the result found
      print(result)

      screen_update_enable()
      screen_update()
    else
        message_box(1, "The key: " .. key_value .. "\n\nwas not found in key list:\n\n" .. table_list(key_values), "Key Not Found")
    end
  else
    message("Operation canelled by user.")
  end
end

key_macro() -- run the macro

Cheers Jussi