}

Golang Index Page 1

golang

SOLVED: function main is undeclared in the main package (Go)

Fix Go error "function main is undeclared in the main package". Causes: wrong package name, missing main(), running go run on wrong file, or build tags.

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golang go type error type conversion interface

Fix 'cannot use X (type Y) as type Z' in Go — Type Mismatch Guide

Fix 'cannot use X (type Y) as type Z' in Go. Covers explicit conversions, interface satisfaction, pointer vs value receivers, and type assertions with the ok pattern.

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golang go rune string unicode utf8 conversion

Go: Convert Rune to String and String to Rune — Complete Guide (2026)

Convert rune to string in Go with string(r). Convert string to rune slice with []rune(s). Covers Unicode, utf8 package, for range iteration, and rune vs byte.

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golang go string int conversion strconv

Go: Convert String to Int (and Int to String) — Complete Guide (2026)

Convert string to int in Go using strconv.Atoi, strconv.ParseInt, fmt.Sscanf. Convert int to string with strconv.Itoa, FormatInt, Sprintf. All methods compared.

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golang go error compile variables blank identifier

Fix 'declared and not used' Error in Go (2026)

Fix Go's 'declared and not used' compile error. Learn why Go enforces this, how to use the blank identifier _, and common cases like loop variables and error returns.

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golang go error compile main package

Fix: "function main is undeclared in the main package" in Go

Fix the Go error "runtime.main_main·f: function main is undeclared in the main package". Covers all 5 causes with code examples and step-by-step solutions.

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golang go modules go.mod go.sum dependencies go mod tidy

go mod tidy Explained: Clean Up Go Module Dependencies (2026)

go mod tidy adds missing and removes unused dependencies from go.mod and go.sum. Learn go mod download, verify, vendor, -e flag, and common post-tidy errors.

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golang go error compile import goimports

Go error: "imported and not used" — Fix Unused Import Compile Error

Fix the Go compiler error "imported and not used". Learn why Go enforces this rule and the 4 ways to resolve it: remove the import, use it, blank import, or goimports.

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golang go error nil pointer panic runtime

Fix 'nil pointer dereference' Panic in Go (2026)

Fix Go's 'nil pointer dereference' runtime panic. Covers nil pointers, nil interfaces, nil maps, uninitialized structs, stack trace reading, and nil-safe patterns.

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golang go error compile undefined import

Fix 'undefined: functionName' Error in Go (2026)

Fix the Go 'undefined: functionName' compile error. Covers wrong package, unexported names, typos, missing imports, and circular imports with before/after code.