Is there a keyword opposite of 'end' when indexing

New to Julia
1

name[end] gives you the last value. But when I learned it, I could’ve sworn there was a keyword for the very first value. Obviously you can just index at one, but does that keyword exist? Or did I make it up?

2

If I recall correctly, that would be ‘’ arrayname[begin], but checking this on my phone is a bit tricky.

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3

While begin and end are used to create a block of code, they can also be used as “indices” to safely get the first and last elements of a collection. While Arrays do index starting at 1, that’s not always the case e.g. OffsetArrays.jl or just because getindex is a function for which an abitrary method could be created e.g. Base.getindex() = 2 (wow I hate that).

From the documentation

begin

  begin...end denotes a block of code.

  begin
      println("Hello, ")
      println("World!")
  end

  Usually begin will not be necessary, since keywords such as function and let implicitly begin blocks of code. See also ;.

  begin may also be used when indexing to represent the first index of a collection or the first index of a dimension of an array. For example, a[begin]
  is the first element of an array a.

  │ Julia 1.4
  │
  │  Use of begin as an index requires Julia 1.4 or later.

  Examples
  ≡≡≡≡≡≡≡≡

  julia> A = [1 2; 3 4]
  2×2 Matrix{Int64}:
   1  2
   3  4

  julia> A[begin, :]
  2-element Matrix{Int64}:
   1
   2

Similarly for end

end

  end marks the conclusion of a block of expressions, for example module, struct, mutable struct, begin, let, for etc.

  end may also be used when indexing to represent the last index of a collection or the last index of a dimension of an array.

  Examples
  ≡≡≡≡≡≡≡≡

  julia> A = [1 2; 3 4]
  2×2 Matrix{Int64}:
   1  2
   3  4

  julia> A[end, :]
  2-element Vector{Int64}:
   3
   4
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