viem-goviem-go

Get Abi Item

Look up a function, event, or error by name or selector from a parsed ABI in viem-go

GetAbiItem finds a function, event, or error on a parsed ABI by name or selector (hex string). For overloaded functions, pass Args to disambiguate. Use the direct lookups (GetFunction, GetEvent, GetError, GetFunctionBySelector, GetEventByTopic, GetErrorBySelector) when you already know the kind of item or the key.

Import

import (
  "math/big"
  "github.com/ethereum/go-ethereum/common"
  "github.com/ChefBingbong/viem-go/abi"
)

GetAbiItem

import "github.com/ChefBingbong/viem-go/abi"


// parsed is *abi.ABI from abi.Parse(...)


// By name
item, err := parsed.GetAbiItem("transfer", nil)


// By selector (4-byte hex or 32-byte event topic hex)
item, err := parsed.GetAbiItem("0xa9059cbb", nil)


// Overloaded function: disambiguate with args
item, err := parsed.GetAbiItem("foo", &abi.GetAbiItemOptions{
  Args: []any{common.HexToAddress("0x..."), big.NewInt(1)},
})


// Type-assert to Function, Event, or Error (or pointer)
switch v := item.(type) {
case abi.Function:
  fmt.Println(v.Signature)
case abi.Event:
  fmt.Println(v.Topic.Hex())
case abi.Error:
  fmt.Println(v.Selector)
}
  • Signature: (a *ABI) GetAbiItem(nameOrSelector string, opts *GetAbiItemOptions) (AbiItem, error)
  • GetAbiItemOptions: Args []any — used to resolve overloads when multiple items share a name.
  • With a 32-byte hex string, matches events by topic; with 8-char hex, matches function/error selectors.

Direct lookups

When you know the item kind or key, use:

  • *GetFunction(name string) (Function, error) — by function name.
  • *GetEvent(name string) (Event, error) — by event name.
  • *GetError(name string) (Error, error) — by error name.
  • *GetFunctionBySelector(selector [4]byte) (Function, error) — by 4-byte selector.
  • *GetEventByTopic(topic common.Hash) (Event, error) — by event topic.
  • *GetErrorBySelector(selector [4]byte) (Error, error) — by 4-byte selector.
fn, err := parsed.GetFunction("transfer")
ev, err := parsed.GetEventByTopic(topic)
errItem, err := parsed.GetErrorBySelector(selector)

Go notes

  • AbiItem is an interface; the concrete value returned may be Function, Event, or Error (value types from the ABI maps). FormatAbiItem and FormatAbiItemWithArgs accept both value and pointer types.

See also