using SafeMath for uint256; uint256 public consecutiveWins; uint256 lastHash; uint256 FACTOR = 57896044618658097711785492504343953926634992332820282019728792003956564819968;
constructor() public { consecutiveWins = 0; }
function flip(bool _guess) public returns (bool) { uint256 blockValue = uint256(blockhash(block.number.sub(1)));
The fallback function is executed on a call to the contract if none of the other functions match the given function signature, or if no data was supplied at all and there is no receive Ether function. The fallback function always receives data, but in order to also receive Ether it must be marked payable.
解决 Apple Silicon (M1) 上 LoadError - dlsym(0x7fbb17932d30, Init_ffi_c): symbol not found - /Library/Ruby/Gems/2.6.0/gems/ffi-1.15.3/lib/ffi_c.bundle 问题。
Fatal error: Bug in WebKit: Received neither result or failure.: file WebKit/WebKitSwiftOverlay.swift, line 66
问题现象
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webView.evaluateJavaScript("console.log('Hello World')", in: nil, in: .page) { result in print(result) }
在 iOS 14.0 的版本中执行以上的代码会产生crash Fatal error: Bug in WebKit: Received neither result or failure.: file WebKit/WebKitSwiftOverlay.swift, line 66 ,但是在最新版 14.5 不会崩溃。
$ otool -L WebKit | grep WebKit [23:42:54] WebKit: /System/Library/Frameworks/WebKit.framework/WebKit (compatibility version 1.0.0, current version 611.1.21) /System/Library/PrivateFrameworks/WebKitLegacy.framework/WebKitLegacy (compatibility version 1.0.0, current version 611.1.21, reexport)