This is a modified binary-to-text decoding used for decoding Bitcoin addresses, aka Base58Check. If this is applied to a WIF address and the first and last four bytes are dropped, the result is the corresponding private key.
base58CheckDecode(x)character, string in hex format.
list, the decoded elements of the string.
https://en.bitcoin.it/wiki/Wallet_import_format, https://en.bitcoin.it/wiki/Address, https://en.bitcoin.it/wiki/Base58Check_encoding
Other BtcAdresses: BTCADR-class,
PrivKey2PubKey, PrivKey2Wif,
PubHash2BtcAdr,
PubKey2PubHash, Wif2PrivKey,
base58CheckEncode, concatHex,
createBtcAdr,
createPrivateKey, decodeHex,
hash160, hash256,
validBtcAdr