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More tweaks to readme, tests, license - ready for mesh release
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‎LICENSE

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All files except
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* the [.sml], [.ml] and [.thy] files in [lem] directory and
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the files in elle/tests
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are distributed under Apache License Version 2.0.
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The [.sml], [.ml] and [.thy] files in [lem] directory are distributed under the terms in [lem/lem-license].
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The files in elle/tests are property of their owners, as described in elle/README.
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Other files in elle/tests are subject to the Apache License Version 2.0.
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Apache License

‎README.md

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@@ -49,7 +49,7 @@ once you have built the `llllc` executable:
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`cd elle/tests`
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`../generated/llllc add.lll`
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`../generated/llllc echo.lll`
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(or any other lll file in the directory)
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‎elle/tests/README

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add.lll - simple addition expression *
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def.lll - macro definition *
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echo.lll - Dan Ellison's echo contract *
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erc20.lll - Ben Edgington's ERC20 token
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echo.lll - Dan Ellison's echo contract (https://media.consensys.net/compiling-your-first-contract-in-lll-28d5a9dd2e3a)*
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erc20.lll - Ben Edgington's ERC20 token (https://github.com/benjaminion/LLL_erc20/blob/master/erc20.lll)
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if.lll, seq.lll, seq2.lll, when.lll - control flow tests *
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raw.lll - "raw" sequencing constrct from lll
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revert.lll - reverting a transaction
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weirdstring.lll - test lll string syntax
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lit.lll - test lll literals
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‎elle/tests/erc20.lll

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;;; ---------------------------------------------------------------------------
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;;; Implementation of an ERC20 Token contract in LLL
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;;;
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;;; Ben Edgington - ben@benjaminion.xyz
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;;;
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(seq
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;; --------------------------------------------------------------------------
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;; CONSTANTS
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;; Token parameters.
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;; 0x40 is a "magic number" - the text of the string is placed here
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;; when returning the string to the caller. See return-string below.
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(def 'token-name-string (lit 0x40 "LLL Coin - love to code in LLL."))
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(def 'token-symbol-string (lit 0x40 "LLL"))
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(def 'token-decimals 0)
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(def 'token-supply 100) ; 100 total tokens
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;; Booleans
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(def 'false 0)
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(def 'true 1)
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;; Memory layout.
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(def 'mem-ret 0x00) ; Fixed due to compiler macro for return.
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(def 'mem-func 0x00) ; No conflict with mem-ret, so re-use.
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(def 'mem-keccak 0x00) ; No conflict with mem-func or mem-ret, so re-use.
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(def 'scratch0 0x20)
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(def 'scratch1 0x40)
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;; Precomputed function IDs.
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(def 'get-name 0x06fdde03) ; name()
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(def 'get-symbol 0x95d89b41) ; symbol()
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(def 'get-decimals 0x313ce567) ; decimals()
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(def 'get-total-supply 0x18160ddd) ; totalSupply()
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(def 'get-balance-of 0x70a08231) ; balanceOf(address)
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(def 'transfer 0xa9059cbb) ; transfer(address,uint256)
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(def 'transfer-from 0x23b872dd) ; transferFrom(address,address,uint256)
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(def 'approve 0x095ea7b3) ; approve(address,uint256)
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(def 'get-allowance 0xdd62ed3e) ; allowance(address,address)
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;; Event IDs
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(def 'transfer-event-id ; Transfer(address,address,uint256)
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0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef)
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(def 'approval-event-id ; Approval(address,address,uint256)
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0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925)
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;; --------------------------------------------------------------------------
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;; UTILITIES
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;; --------------------------------------------------------------------------
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;; The following define the key data-structures:
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;; - balance(addr) => value
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;; - allowance(addr,addr) => value
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;; Balances are stored at s[owner_addr].
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(def 'balance (address) address)
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;; Allowances are stored at s[owner_addr + keccak256(spender_addr)]
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;; We use a crypto function here to avoid any situation where
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;; approve(me, spender) can be abused to do approve(target, me).
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(def 'allowance (owner spender)
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(seq
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(mstore mem-keccak spender)
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(add owner (keccak256 mem-keccak 0x20))))
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;; --------------------------------------------------------------------------
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;; For convenience we have macros to refer to function arguments
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(def 'arg1 (calldataload 0x04))
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(def 'arg2 (calldataload 0x24))
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(def 'arg3 (calldataload 0x44))
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;; --------------------------------------------------------------------------
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;; Revert is a soft return that does not consume the remaining gas.
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;; We use it when rejecting invalid user input.
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;;
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;; Note: The REVERT opcode will be implemented in Metropolis (EIP 140).
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;; Meanwhile it just causes an invalid instruction exception (similar
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;; to a "throw" in Solidity). When fully implemented, Revert could be
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;; use to return error codes, or even messages.
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(def 'revert () (revert 0 0))
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;; --------------------------------------------------------------------------
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;; Macro for returning string names.
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;; Compliant with the ABI format for strings.
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(def 'return-string (string-literal)
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(seq
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(mstore 0x00 0x20) ; Points to our string's memory location
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(mstore 0x20 string-literal) ; Length. String itself is copied to 0x40.
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(return 0x00 (& (+ (mload 0x20) 0x5f) (~ 0x1f)))))
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; Round return up to 32 byte boundary
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;; --------------------------------------------------------------------------
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;; Convenience macro for raising Events
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(def 'event3 (id addr1 addr2 value)
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(seq
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(mstore scratch0 value)
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(log3 scratch0 0x20 id addr1 addr2)))
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;; --------------------------------------------------------------------------
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;; Determines whether the stored function ID matches a known
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;; function hash and executes <code-body> if so.
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;; @param function-hash The four-byte hash of a known function signature.
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;; @param code-body The code to run in the case of a match.
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(def 'function (function-hash code-body)
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(when (= (mload mem-func) function-hash)
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code-body))
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;; --------------------------------------------------------------------------
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;; Gets the function ID and stores it in memory for reference.
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;; The function ID is in the leftmost four bytes of the call data.
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(def 'uses-functions
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(seq
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(mstore mem-func 0)
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(calldatacopy (+ mem-func 28) 0x00 4)))
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;; --------------------------------------------------------------------------
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;; GUARDS
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;; --------------------------------------------------------------------------
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;; Checks that ensure that each function is called with the right
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;; number of arguments. For one thing this addresses the "ERC20
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;; short address attack". For another, it stops me making
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;; mistakes while testing. We use these only on the non-constant functions.
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(def 'has-one-arg (unless (= 0x24 (calldatasize)) (revert)))
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(def 'has-two-args (unless (= 0x44 (calldatasize)) (revert)))
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(def 'has-three-args (unless (= 0x64 (calldatasize)) (revert)))
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;; --------------------------------------------------------------------------
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;; Check that addresses have only 160 bits and revert if not.
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;; We use these input type-checks on the non-constant functions.
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(def 'is-address (addr)
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(when
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(shr addr 160)
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(revert)))
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;; --------------------------------------------------------------------------
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;; Check that transfer values are smaller than total supply and
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;; revert if not. This should effectively exclude negative values.
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(def 'is-value (value)
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(when (> value token-supply) (revert)))
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;; --------------------------------------------------------------------------
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;; Will revert if sent any Ether. We use the macro immediately so as
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;; to abort if sent any Ether during contract deployment.
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(def 'not-payable
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(when (callvalue) (revert)))
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not-payable
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;; --------------------------------------------------------------------------
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;; INITIALISATION
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;;
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;; Assign all tokens initially to the owner of the contract.
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(sstore (balance (caller)) token-supply)
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;; --------------------------------------------------------------------------
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;; CONTRACT CODE
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(returnlll
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(seq not-payable uses-functions
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;; ----------------------------------------------------------------------
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;; Getter for the name of the token.
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;; @abi name() constant returns (string)
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;; @return The token name as a string.
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(function get-name
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(return-string token-name-string))
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;; ----------------------------------------------------------------------
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;; Getter for the symbol of the token.
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;; @abi symbol() constant returns (string)
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;; @return The token symbol as a string.
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(function get-symbol
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(return-string token-symbol-string))
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;; ----------------------------------------------------------------------
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;; Getter for the number of decimals assigned to the token.
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;; @abi decimals() constant returns (uint256)
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;; @return The token decimals.
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(function get-decimals
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(return token-decimals))
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;; ----------------------------------------------------------------------
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;; Getter for the total token supply.
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;; @abi totalSupply() constant returns (uint256)
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;; @return The token supply.
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(function get-total-supply
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(return token-supply))
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;; ----------------------------------------------------------------------
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;; Returns the account balance of another account.
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;; @abi balanceOf(address) constant returns (uint256)
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;; @param owner The address of the account's owner.
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;; @return The account balance.
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(function get-balance-of
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(seq
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(def 'owner arg1)
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(return (sload (balance owner)))))
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;; ----------------------------------------------------------------------
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;; Transfers _value amount of tokens to address _to. The command
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;; should throw if the _from account balance has not enough
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;; tokens to spend.
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;; @abi transfer(address, uint256) returns (bool)
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;; @param to The account to receive the tokens.
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;; @param value The quantity of tokens to transfer.
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;; @return Success (true). Other outcomes result in a Revert.
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(function transfer
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(seq has-two-args (is-address arg1) (is-value arg2)
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(def 'to arg1)
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(def 'value arg2)
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(when value ; value == 0 is a no-op
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(seq
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;; The caller's balance. Save in memory for efficiency.
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(mstore scratch0 (sload (balance (caller))))
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;; Revert if the caller's balance is not sufficient.
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(when (> value (mload scratch0))
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(revert))
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;; Make the transfer
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;; It would be good to check invariants (sum of balances).
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(sstore (balance (caller)) (- (mload scratch0) value))
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(sstore (balance to) (+ (sload (balance to)) value))
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;; Event - Transfer(address,address,uint256)
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(event3 transfer-event-id (caller) to value)))
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(return true)))
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;; ----------------------------------------------------------------------
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;; Send _value amount of tokens from address _from to address _to
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;; @abi transferFrom(address,address,uint256) returns (bool)
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;; @param from The account to send the tokens from.
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;; @param to The account to receive the tokens.
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;; @param value The quantity of tokens to transfer.
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;; @return Success (true). Other outcomes result in a Revert.
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(function transfer-from
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(seq has-three-args (is-address arg1) (is-address arg2) (is-value arg3)
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(def 'from arg1)
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(def 'to arg2)
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(def 'value arg3)
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(when value ; value == 0 is a no-op
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(seq
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;; Save data to memory for efficiency.
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(mstore scratch0 (sload (balance from)))
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(mstore scratch1 (sload (allowance from (caller))))
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;; Revert if not enough funds, or not enough approved.
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(when
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(||
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(> value (mload scratch0))
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(> value (mload scratch1)))
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(revert))
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;; Make the transfer and update allowance.
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(sstore (balance from) (- (mload scratch0) value))
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(sstore (balance to) (+ (sload (balance to)) value))
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(sstore (allowance from (caller)) (- (mload scratch1) value))
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;; Event - Transfer(address,address,uint256)
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(event3 transfer-event-id from to value)))
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(return true)))
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;; ----------------------------------------------------------------------
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;; Allows _spender to withdraw from your account multiple times,
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;; up to the _value amount. If this function is called again it
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;; overwrites the current allowance with _value.
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;; @abi approve(address,uint256) returns (bool)
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;; @param spender The withdrawing account having its limit set.
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;; @param value The maximum allowed amount.
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;; @return Success (true). Other outcomes result in a Revert.
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(function approve
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(seq has-two-args (is-address arg1) (is-value arg2)
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(def 'spender arg1)
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(def 'value arg2)
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;; Force users set the allowance to 0 before setting it to
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;; another value for the same spender. Prevents this attack:
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;; https://docs.google.com/document/d/1YLPtQxZu1UAvO9cZ1O2RPXBbT0mooh4DYKjA_jp-RLM
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(when
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(&& value (sload (allowance (caller) spender)))
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(revert))
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(sstore (allowance (caller) spender) value)
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;; Event - Approval(address,address,uint256)
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(event3 approval-event-id (caller) spender value)
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(return true)))
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;; ----------------------------------------------------------------------
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;; Returns the amount which _spender is still allowed to withdraw
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;; from _owner.
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;; @abi allowance(address,address) constant returns (uint256)
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;; @param owner The owning account.
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;; @param spender The withdrawing account.
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;; @return The allowed amount remaining.
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(function get-allowance
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(seq
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(def 'owner arg1)
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(def 'spender arg2)
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(return (sload (allowance owner spender)))))
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;; ----------------------------------------------------------------------
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;; Fallback: No functions matched the function ID provided.
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(revert)))
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)

‎elle/tests/weirdstring.lll

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