I’d like to use ‘+’ operator for string concatenation. but it is ‘*’ in Julia. If possible I’d like to define ‘+’ as alias of ‘*’ if opland are strings. because some insufficient definition cause some side effect. Thanks in advance!!

See also the Julia FAQ: Why does Julia use * for string concatenation? Why not + or something else? In general, when you learn a new language, you should try to learn the idiomatic “spelling” of things in that language. Trying to write code in Julia that superficially resembles some other language…

No, that would be type piracy. Do not do this!

Of course, you can: Base.:+(a::String, b::String)=a*b But there is a clear mathematical reason for the choice in Julia: generally, “+” is considered to be always commutative, while “*” (e.g. for matrices) may be not commutative, and string concatenation is clearly not commutative. Also, yes, this…

It is however possible to create your own string type with whatever properties you like, without breaking any norms like “type piracy”: struct MyString <: AbstractString s::String end macro s_str(e) :(MyString($e)) end Base.getindex(s::MyString, arg::Int) = getindex(s.s, arg) Base.iterate…

It’s even easier to create your own +! No piracy, and you don’t need to forward all the other string methods. julia> a::String + b::String = a * b # may need to restart the session for this line to work + (generic function with 1 method) julia> "a" + "b" "ab" julia> 2 + 2 ERROR: MethodError: no …

Thank you j-fu for your code and your advice. I found that your code works well for me. but “+” looks more natural operator for string concatenation I suppose…

Thank you for your suggestion cstjean. I learned a lot from your code. I appreciate it!!

Well, but ‘*’ looks strange for me… thanks anyway

I understand your point. thank you for your information. but I am going to use my code for internal use only.

thanks sgaure, maybe you are genius! Although I will use j-fu method for now, I might use your method in some other issues.

Take also a look at this thread and the tiny Julia package PlusPlus.jl with just three lines of code.

Is it possible to define '+' operator for string as '*' do for them?

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Is it possible to define '+' operator for string as '*' do for them?

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