go-naming

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name: go-naming description: Use when naming any Go identifier — packages, types, functions, methods, variables, constants, or receivers — to ensure idiomatic, clear names. Also use when a user is creating new types, packages, or exported APIs, even if they don't explicitly ask about naming conventions. Does not cover package organization (see go-packages). allowed-tools: Bash(bash:*)

Go Naming Conventions

Resource Routing

• scripts/check-naming.sh - Run when checking SCREAMING_SNAKE_CASE constants, Get-prefixed getters, generic package names, or receivers named this/self.
• references/IDENTIFIERS.md - Read when choosing names for initialisms, exported identifiers, or package-level symbols.
• references/REPETITION.md - Read when names repeat package, receiver, type, or local context.
• references/VARIABLES.md - Read when choosing local variable names, receiver names, or loop identifiers.

Core Principle

Names should:

• Not feel repetitive when used
• Take context into consideration
• Not repeat concepts that are already clear

Naming is more art than science—Go names tend to be shorter than in other languages.

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Naming Decision Flow

What are you naming?
├─ Package       → Short, lowercase, singular noun (no underscores, no mixedCaps)
├─ Interface     → Method name + "-er" suffix when single-method (Reader, Writer)
├─ Receiver      → 1-2 letter abbreviation of type (c for Client); consistent across methods
├─ Constant      → MixedCaps; use iota for enums; no ALL_CAPS
├─ Exported func → Verb or verb-phrase in MixedCaps; no Get prefix for getters
├─ Variable      → Length proportional to scope distance
│                  ├─ Tiny scope (1-7 lines) → single letter (i, n, r)
│                  ├─ Medium scope           → short word (count, buf)
│                  └─ Package-level / wide   → descriptive (userAccountCount)
└─ Any name      → Check: does it repeat package name or context? If yes, shorten it

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MixedCaps (Required)

Normative: All Go identifiers must use MixedCaps.

Underscores are allowed only in: test functions (TestFoo_InvalidInput), generated code, and OS/cgo interop.

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Package Names

Normative: Packages must be lowercase with no underscores.

Short, lowercase, singular nouns. Avoid generic names like util, common, helper — prefer specific names: stringutil, httpauth, configloader.

// Good: user, oauth2, tabwriter
// Bad:  user_service, UserService, count (shadows var)

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Interface Names

Advisory: One-method interfaces use "-er" suffix.

Name one-method interfaces by the method plus -er: Reader, Writer, Formatter. Honor canonical method names (Read, Write, Close, String) and their signatures.

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Receiver Names

Normative: Receivers must be short abbreviations, used consistently.

One or two letters abbreviating the type, consistent across all methods: func (c *Client) Connect(), func (c *Client) Send(). Never use this or self.

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Constant Names

Normative: Constants use MixedCaps, never ALL_CAPS or K prefix.

Name constants by role, not value: MaxRetries not Three, DefaultPort not Port8080.

const MaxPacketSize = 512
const defaultTimeout = 30 * time.Second

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Initialisms and Acronyms

Normative: Initialisms maintain consistent case throughout.

Initialisms (URL, ID, HTTP, API) must be all uppercase or all lowercase: HTTPClient, userID, ParseURL() — not HttpClient, orderId, ParseUrl().

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Function and Method Names

Advisory: No Get prefix for simple accessors; use verb-like names for actions.

Getter for field owner is Owner(), not GetOwner(). Setter is SetOwner(). Use Compute or Fetch for expensive operations.

When functions differ only by type, include type at the end: ParseInt(), ParseInt64().

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Variable Names

Variable naming balances brevity with clarity. Key principles:

• Scope-based length: Short names (i, v) for small scopes; longer, descriptive names for larger scopes
• Single-letter conventions: Use familiar patterns (i for index, r/w for reader/writer)
• Avoid type in name: Use users not userSlice, name not nameString
• Prefix unexported globals: Use _ prefix for package-level unexported vars/consts to prevent shadowing

for i, v := range items { ... }           // small scope
pendingOrders := filterPending(orders)    // larger scope
const _defaultPort = 8080                 // unexported global

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Avoiding Repetition

Go names should not feel repetitive when used. Consider the full context:

• Package + symbol: widget.New() not widget.NewWidget()
• Receiver + method: p.Name() not p.ProjectName()
• Context + type: In package sqldb, use Connection not DBConnection

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Avoid Built-In Names

Never shadow Go's predeclared identifiers (error, string, len, cap, append, copy, new, make, etc.) as variable, parameter, or type names.

For detailed guidance: See go-declarations — "Avoid Using Built-In Names" section.

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Quick Reference

Element	Rule	Example
Package	lowercase, no underscores	package httputil
Exported	MixedCaps, starts uppercase	func ParseURL()
Unexported	mixedCaps, starts lowercase	func parseURL()
Receiver	1-2 letter abbreviation	func (c *Client)
Constant	MixedCaps, never ALL_CAPS	const MaxSize = 100
Initialism	consistent case	userID, XMLAPI
Variable	length ~ scope size	i (small), userCount (large)
Built-in names	Never shadow predeclared identifiers	See go-declarations

Validation: After renaming identifiers, run bash scripts/check-naming.sh to verify no naming anti-patterns remain. Then run go build ./... to confirm the rename didn't break anything.

Related Skills

• Interface naming: See go-interfaces when naming interfaces with the -er suffix or choosing receiver types
• Package naming: See go-packages when naming packages, avoiding util/common, or resolving import collisions
• Error naming: See go-error-handling when naming sentinel errors (ErrFoo) or custom error types
• Declaration scope: See go-declarations when variable name length depends on scope or when avoiding built-in shadowing
• Style principles: See go-style-core when balancing clarity vs concision in identifier names