go - Why are struct literals "literal" -

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in golang struct literals?

why following literal though there variable? , aren't structs literally variable, when not const? how make sense.

mytype{field: var)

it has variable , yet it's "literal"?

also why called "struct literal" when first initialize it?

programming languages use word "literal" when referring sytactic ways construct data structure. means it's not constructed creating empty 1 , adding or subtracting go.

compare:

mytype{field: myvariable}

to

var x = new(mytype) x.field = myvariable

the benefit code's appearance reflects data structure in way. downside have know layout in advance , have content initialized already, not possible, if instance, you're constructing map unknown keys.


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