# Ways of defining a function
**URL:** https://discourse.julialang.org/t/ways-of-defining-a-function/3465
**Category:** General Usage
**Tags:** question
**Created:** [May 1, 2017, 6:09pm UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465 "2017-05-01T18:09:05Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@jw3126](https://discourse.julialang.org/u/jw3126)
#### Post date: [May 1, 2017, 6:09pm UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/1 "2017-05-01T18:09:05Z")
Most julia functions are defined like this:
```nohighlight
function f(x)
# some code
end
```
However a few packages use the following style
```nohighlight
f(x) = begin
# some code
end
```
Is there a semantic difference between the two or are they exactly the same?
---
### Author:  [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)
#### Post date: [May 1, 2017, 6:20pm UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/2 "2017-05-01T18:20:09Z")
```julia
f(x) = ...
```
is just shorthand for
```julia
function f(x)
...
end
```
That said, using the shorthand with a `begin ... end` block just defeats its purpose. Use it when your code is short (one-liners).
---
### Author:  [@jw3126](https://discourse.julialang.org/u/jw3126)
#### Post date: [May 1, 2017, 6:28pm UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/3 "2017-05-01T18:28:58Z")
Ok do I get this right:
- `function f(x) ... end`
- `f(x) = begin ... end`
- `f(x) = let ... end`
- `f(x) = ... `
are all lowered to exactly the same thing? Analogous for more complicated signatures like `f(x::Int,y::T; kw...) where T`?
---
### Author:  [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)
#### Post date: [May 1, 2017, 7:06pm UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/4 "2017-05-01T19:06:07Z")
`let` has different [scoping behavior](https://docs.julialang.org/en/latest/manual/variables-and-scoping.html), but other than that, yes. Note that the answer to your question is in the [documentation](https://docs.julialang.org/en/latest/manual/functions.html), so please try to read that.
---
### Author:  [@fengyang.wang](https://discourse.julialang.org/u/fengyang.wang)
#### Post date: [May 1, 2017, 7:50pm UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/5 "2017-05-01T19:50:56Z")
Some authors may be influenced by the Scala style guide, which suggests that pure functions be written with the Scala equivalent of `f(x) = ...`, and impure functions be written as `function f(x) ... end` regardless of how many lines `...` requires. Since this style is clear and useful, despite not being prevalent, I would personally suggest that it’s up to you whether to use `begin ... end`.
---
### Author:  [@jw3126](https://discourse.julialang.org/u/jw3126)
#### Post date: [May 1, 2017, 9:21pm UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/6 "2017-05-01T21:21:46Z")
Can you give an example, when
`f(x) = begin ... end`
`f(x) = let ... end`
differ?
---
### Author:  [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)
#### Post date: [May 2, 2017, 6:26am UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/7 "2017-05-02T06:26:09Z")
The function definition already introduces hard scope, so in this case they don’t differ. My point was about `let` in general; I only use it when I want its specific scoping behavior, but in your example it does not make a difference.
---
### Author:  [@Evizero](https://discourse.julialang.org/u/Evizero)
#### Post date: [May 2, 2017, 10:14am UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/8 "2017-05-02T10:14:35Z")
``
Can we please **not** promote this style
```julia
f(x) = begin
# multiline code
end
```
``
---
### Author:  [@pint](https://discourse.julialang.org/u/pint)
#### Post date: [May 2, 2017, 11:12am UTC](https://discourse.julialang.org/t/ways-of-defining-a-function/3465/9 "2017-05-02T11:12:43Z")
i do like this style. primarily because
1, i don’t like that there are two syntaxes for the same thing
2, i often find myself changing back and force between a one liner and a few liner, or ? vs if, as the code develops. it is a hassle to restructure.
so i usually just use f() = … exclusively