Go Style: Difference between revisions
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=Internal= | =Internal= | ||
* [[Go Engineering]] | * [[Go Engineering]] | ||
* [[Go_Language#Source_Code_Formatting|Go Source Code Formatting]] | |||
* [[Go_fmt#Overview|<tt>gofmt</tt>]] | |||
=Overview= | =Overview= | ||
The [[Go_Language_Modularization#Standard_library|Go standard library]] is a good source of code examples, comments and style. | The [[Go_Language_Modularization#Standard_library|Go standard library]] is a good source of code examples, comments and style. | ||
=Line Length= | |||
Go has no line length limit. However, if the line feels too long, wrap it and indent it with an extra tab. | |||
=Comments= | |||
{{Internal|Go_Language#Comments|Go Language | Comments}} | |||
=<span id='Identifiers'></span>Naming= | =<span id='Identifiers'></span>Naming= | ||
{{External|https://google.github.io/styleguide/go/guide#mixedcaps}} | {{External|https://google.github.io/styleguide/go/guide#mixedcaps}} | ||
Naming is one of the most important aspects of Go development. Writing idiomatic Go requires understanding of its core naming principles. | Naming is one of the most important aspects of Go development. Writing idiomatic Go requires understanding of its core naming principles. The following rules apply to [[Go_Constants#Overview|constant]] and [[Go_Variables#Overview|variable]] [[Go_Language#Identifiers_(Names)|identifiers]], function names, type names, like struct or interface names. | ||
Names have a semantic effect. The visibility of a name outside a package is determined whether its first character is upper case. See: {{Internal|Go_Language#Exported_Identifiers|Exported Identifiers}} | |||
Go style recommends camel-case (mixed-case) for identifiers, rather than snake-case (underscore) to write multi-word names. Use <code>SomeVariable</code> or <code>someVariable</code>, depending on whether the variable is visible outside the package or not. Do not use snake case <code>some_variable</code>. Every exported name should be [[Go_Language#Comments|documented with a comment]]. | |||
Names, and in special variable names, should be short rather than long. Long names do not automatically make things more readable. A helpful doc comment can often be more valuable than an extra long name. | |||
Acronyms should have a consistent case. <code>URL</code> or <code>url</code> is correct, <code>Url</code> is not. Prefer all-capital acronyms, if it makes sense (<code>URL</code>). | |||
Use name abbreviations only if they are widely used (example: <code>fmt</code>). Avoid name collisions, when possible. If you introduce a set of string functions, avoid calling the package <code>strings</code> because a package with the same name exists in the standard library already. | |||
When a feature is imported from another package, its name includes the package name or alias: <code>mypackage.MyVar</code>. This is a reason to [[Go_Packages#Try_to_Make_Package_Names_and_Exported_Names_Work_Together|try to make the package name and the feature name work together]]. | |||
The greater the distance between a name's declaration and its uses, the longer the name should be. | |||
Where more specific rules apply to a particular kind of name, those rules are documented in a dedicated style section: | |||
==Constants== | |||
{{Internal|Go_Constants#Naming|Constants Naming}} | |||
==Variables== | |||
{{Internal|Go_Variables#Naming|Variables Naming}} | |||
==Packages== | |||
{{Internal|Go_Packages#Package_Name|Package Names}} | |||
==Interfaces== | |||
{{Internal|Go_Interfaces#Idiomatic_Interface_Conventions|Interfaces}} | |||
==Source Files== | |||
{{Internal|Go_Language#Source_File_Name_Conventions|Source File Naming}} | |||
==Functions== | |||
{{Internal|Go_Functions#Naming|Function Naming}} | |||
===Receivers=== | |||
{{Internal|Go_Language_Object_Oriented_Programming#Receiver_Naming|Receiver Naming}} | |||
===Methods=== | |||
{{Internal|Go_Language_Object_Oriented_Programming#Method_Naming|Method Naming}} | |||
===Getters and Setters=== | |||
{{External|https://go.dev/doc/effective_go#Getters}} | |||
Go does not provide automatic support for getters and setters, but there is nothing wrong with programming getters and setters yourself. | |||
These are the conventions around naming the getters and setters, documented in [https://go.dev/doc/effective_go#Getters effective_go]: | |||
* The field should be [[Go_Packages#Unexported_Members|unexported]] (lower-case name). Example: <code>name</code>. | |||
* The getter method should have the same name as the field, except the for the first character, which is upper-case, making it exported. Example: <code>Name()</code>. It is neither idiomatic, not necessary to put "Get" in the getter's name. The method '''should not''' be called <code>GetName()</code>. | |||
* The setter method should be called <code>SetOwner()</code>. | |||
<syntaxhighlight lang='go'> | |||
type SomeStruct struct { | |||
name string // unexported | |||
} | |||
// Name is the getter method, exported. Must not be called GetName() | |||
func (s *SomeStruct) Name() string { | |||
return s.name | |||
} | |||
// SetName is the setter method, exported | |||
func (s *SomeStruct) SetName(name string) { | |||
s.name = name | |||
} | |||
</syntaxhighlight> | |||
=Idiomatic Error Handling= | |||
{{Internal|Go_Language_Error_Handling#Idiomatic_Error_Handling|Idiomatic Error Handling}} | |||
Latest revision as of 23:52, 5 July 2024
External
- https://google.github.io/styleguide/go/
- https://go.dev/doc/effective_go
- https://github.com/golang/go/wiki/CodeReviewComments
Internal
Overview
The Go standard library is a good source of code examples, comments and style.
Line Length
Go has no line length limit. However, if the line feels too long, wrap it and indent it with an extra tab.
Comments
Naming
Naming is one of the most important aspects of Go development. Writing idiomatic Go requires understanding of its core naming principles. The following rules apply to constant and variable identifiers, function names, type names, like struct or interface names.
Names have a semantic effect. The visibility of a name outside a package is determined whether its first character is upper case. See:
Go style recommends camel-case (mixed-case) for identifiers, rather than snake-case (underscore) to write multi-word names. Use SomeVariable
or someVariable
, depending on whether the variable is visible outside the package or not. Do not use snake case some_variable
. Every exported name should be documented with a comment.
Names, and in special variable names, should be short rather than long. Long names do not automatically make things more readable. A helpful doc comment can often be more valuable than an extra long name.
Acronyms should have a consistent case. URL
or url
is correct, Url
is not. Prefer all-capital acronyms, if it makes sense (URL
).
Use name abbreviations only if they are widely used (example: fmt
). Avoid name collisions, when possible. If you introduce a set of string functions, avoid calling the package strings
because a package with the same name exists in the standard library already.
When a feature is imported from another package, its name includes the package name or alias: mypackage.MyVar
. This is a reason to try to make the package name and the feature name work together.
The greater the distance between a name's declaration and its uses, the longer the name should be.
Where more specific rules apply to a particular kind of name, those rules are documented in a dedicated style section:
Constants
Variables
Packages
Interfaces
Source Files
Functions
Receivers
Methods
Getters and Setters
Go does not provide automatic support for getters and setters, but there is nothing wrong with programming getters and setters yourself.
These are the conventions around naming the getters and setters, documented in effective_go:
- The field should be unexported (lower-case name). Example:
name
. - The getter method should have the same name as the field, except the for the first character, which is upper-case, making it exported. Example:
Name()
. It is neither idiomatic, not necessary to put "Get" in the getter's name. The method should not be calledGetName()
. - The setter method should be called
SetOwner()
.
type SomeStruct struct {
name string // unexported
}
// Name is the getter method, exported. Must not be called GetName()
func (s *SomeStruct) Name() string {
return s.name
}
// SetName is the setter method, exported
func (s *SomeStruct) SetName(name string) {
s.name = name
}