Trying to make function which takes string as input and returns no. of words in whole string

Question

**It takes Input as a string such as this - \'Nice one\' And Output gives - 4,3 (which is no. Of words in sentence or string) **

function countx(str)
   local cou         


        

Answer 1

-- Localise for performance.
local insert = table.insert

local text = 'I am a poor boy straight. I do not need sympathy'

local function word_lengths (text)
    local lengths = {}
    for word in text:gmatch '[%l%u]+' do
        insert (lengths, word:len())
    end
    return lengths
end

print ('{' .. table.concat (word_lengths (text), ', ') .. '}')

• gmatch returns an iterator over matches of a pattern in a string.
• [%l%u]+ is a Lua regular expression (see http://lua-users.org/wiki/PatternsTutorial) matching at least one lowercase or uppercase letter:
  • [] is a character class: a set of characters. It matches anything inside brackets, e.g. [ab] will match both a and b,
  • %l is any lowercase Latin letter,
  • %u is any uppercase Latin letter,
  • + means one or more repeats.

Therefore, text:gmatch '[%l%u]+' will return an iterator that will produce words, consisting of Latin letters, one by one, until text is over. This iterator is used in generic for (see https://www.lua.org/pil/4.3.5.html); and on any iteration word will contain a full match of the regular expression.