Creating a new tuple from an existing one

General Usage
1

Is there a general way to create a new tuple from an existing one of any length where one the element is set to something else?

2

One conceptually simple way (for named tuples) is

julia> nt = (a=2, b=3, c=4)
(a = 2, b = 3, c = 4)

julia> nt2 = (nt..., b=10)
(a = 2, b = 10, c = 4)
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3

There is Base.setindex:

julia> tup = (1, 2, 3)

julia> Base.setindex(tup, "abc", 2)
(1, "abc", 3)

Also, Accessors.jl is the package to do similar things, if more functionality is needed:

julia> using Accessors

julia> tup = (1, 2, 3)

julia> @set tup[2] = "abc"
(1, "abc", 3)

julia> @insert tup[2] = "abc"
(1, "abc", 2, 3)
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4

Great. Is there a similar way for unnamed tuples as well?

5

Oh, sorry, I misread your question and thought you were interested in the named tuple case. For regular tuples I don’t know a nice oneliner from the top of my head.

6 
newtup(x,i,y) = (x[1:i-1]...,y,x[i+1:end]...)
newtup((1,2,3,4,5,6,7,8,9,10), 3, 11)

this seems to work

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