EASY: Length of table - how to count?

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• ar2rsawseen Maintainer

  November 2012

  local cnt = #actors

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• Mells Guru

  November 2012 edited November 2012

  Google -> lua table length

  local count = #actors

  Lua.org

  
  The length of a table t is defined to be any integer index n such that t[n] is not nil and t[n+1] is nil; moreover, if t[1] is nil, n can be zero. For a regular array, with non-nil values from 1 to a given n, its length is exactly that n, the index of its last value. If the array has "holes" (that is, nil values between other non-nil values), then #t can be any of the indices that directly precedes a nil value (that is, it may consider any such nil value as the end of the array).

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• david19801 Member

  November 2012

  Thanks guys!

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• OZApps Guru

  November 2012

  @david, if you use

  table.insert

  then this works fine, however if you use names key value pairs or a zero index or a gap in the items,

  #actors

  will not return the correct length. The other way is to count them yourself by iterating through the list using

  pairs

  and if you want to count only the index type irrespective of the gaps in between, use the

  ipairs

  to iterate through the contents.

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