What is the different between make() and {} to initialize a map

[Isaac Mosquera]

Is there a difference between the following 2 lines of code:

m := make(map[string]int)

and the following: 

m := map[string]int{}

are they initialized the same? is one preferred over another?

[Brad Fitzpatrick]

They're the same.

The make form lets you say:

 m := make(map[string]int, 100)

Where 100 is the expected capacity.

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[andrey mirtchovski]

> They're the same.
>
> The make form lets you say:
>
> m := make(map[string]int, 100)
>
> Where 100 is the expected capacity.

and the other form allows you to set some of the elements in the map
"using the usual composite literal syntax with colon-separated
key-value pairs": http://golang.org/doc/effective_go.html#maps

[Kyle Lemons]

On Thu, Sep 5, 2013 at 1:13 PM, Isaac Mosquera <is...@sharethis.com> wrote:

Similar to new(Struct) vs Struct{}, I use them in slightly different ways:

1) If the value is done and I don't need to add anything to it before releasing it off into the world, I use the {} version

2) If I'm planning on adding things to it (usually programmatically) I use the make() (or new()) version.

The idea is that this hints to me in the future where to add new starter values to it.  In (1), I insert them between the braces, in (2) I add them in code somewhere.

YMMV

[Kyle Lemons]

On Fri, Sep 6, 2013 at 11:12 AM, Kyle Lemons <kev...@google.com> wrote:

On Thu, Sep 5, 2013 at 1:13 PM, Isaac Mosquera <is...@sharethis.com> wrote:

Is there a difference between the following 2 lines of code:

m := make(map[string]int)

and the following: 

m := map[string]int{}

are they initialized the same? is one preferred over another?

Similar to new(Struct) vs Struct{}, I use them in slightly different ways:

vs &Struct{}, sorry