# Extend Base.&

**URL:** <https://discourse.julialang.org/t/extend-base/4966>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [July 20, 2017, 3:18am UTC](https://discourse.julialang.org/t/extend-base/4966 "2017-07-20T03:18:19Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Trevor\_Black](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/trevor_black/32/1392_2.png) [@Trevor\_Black](https://discourse.julialang.org/u/Trevor_Black)\
**Post date:** [July 20, 2017, 3:18am UTC](https://discourse.julialang.org/t/extend-base/4966/1 "2017-07-20T03:18:19Z")

</div>

Is it possible to extend Base.&.

i.e.

```julia
function &(my_stuct_a, my_struct_b)
    # Some Code
end

```

It throws error

```julia
ERROR: syntax: expected "(" in function definition

```

And then, attempting

```julia
function Base.&(my_stuct_a, my_struct_b)
    # Some Code
end

Error: syntax: expected "end" in definition of function "Base"

```

---

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**Author:** ![ScottPJones](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/scottpjones/32/146_2.png) [@ScottPJones](https://discourse.julialang.org/u/ScottPJones)\
**Post date:** [July 20, 2017, 3:23am UTC](https://discourse.julialang.org/t/extend-base/4966/2 "2017-07-20T03:23:58Z")

</div>

Yes, but you need to have `Base.:&` for it to work.

---

<div class="post-metadata">

**Author:** ![DrKrar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/drkrar/32/3801_2.png) [@DrKrar](https://discourse.julialang.org/u/DrKrar)\
**Post date:** [July 29, 2017, 5:49pm UTC](https://discourse.julialang.org/t/extend-base/4966/3 "2017-07-29T17:49:19Z")

</div>

> [@Trevor\_Black](#):
>
> is it possible to extend Base.&.

yes,  
but you should import it first

> julia\> import Base: (&)
> 
> julia\> function (&)(my\_stuct\_a, my\_struct\_b)  
> # some code  
> end  
> & (generic function with 17 methods)

---

<div class="post-metadata">

**Author:** ![nalimilan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nalimilan/32/147_2.png) [@nalimilan](https://discourse.julialang.org/u/nalimilan)\
**Post date:** [July 30, 2017, 2:30pm UTC](https://discourse.julialang.org/t/extend-base/4966/4 "2017-07-30T14:30:27Z")

</div>

You can also do:

```julia
function Base.:&(a::String, b::String)
...
end

```