specifications

问题 Below is a syntactically valid javascript program – only, it doesn't behave quite the way we're expecting. The title of the question should help your eyes zoom to The Problem Area const recur = (...args) => ({ type: recur, args }) const loop = f => { let acc = f () while (acc.type === recur) acc = f (...acc.args) return acc } const repeat = n => f => x => loop ((n = n, f = f, x = x) => // The Problem Area n === 0 ? x : recur (n - 1, f, f (x))) console.time ('loop/recur') console.log (repeat

问题 Below is a syntactically valid javascript program – only, it doesn't behave quite the way we're expecting. The title of the question should help your eyes zoom to The Problem Area const recur = (...args) => ({ type: recur, args }) const loop = f => { let acc = f () while (acc.type === recur) acc = f (...acc.args) return acc } const repeat = n => f => x => loop ((n = n, f = f, x = x) => // The Problem Area n === 0 ? x : recur (n - 1, f, f (x))) console.time ('loop/recur') console.log (repeat

问题 Given an object obj is there a guarantee that uintptr(unsafe.Pointer(&obj)) will always evaluate to the same value regardless of when it is called? Of course, Go guarantees that if you take two pointers to the same object, they will always compare equal. It might be possible though that an implementation moves an object in memory and transparently updates all pointers to it. This is interesting if you consider garbage collection strategies like Mark-and-Compact. Would an implementor be

问题 Given an object obj is there a guarantee that uintptr(unsafe.Pointer(&obj)) will always evaluate to the same value regardless of when it is called? Of course, Go guarantees that if you take two pointers to the same object, they will always compare equal. It might be possible though that an implementation moves an object in memory and transparently updates all pointers to it. This is interesting if you consider garbage collection strategies like Mark-and-Compact. Would an implementor be

问题 This question already has answers here : Are there limits to the number of properties in a JavaScript object? (6 answers) Closed 8 days ago . I'm aware that the ECMA script spec says that an object can have infinite children however I also understand many ECMA script implementations do not conform to this. I was wondering if node has a limit on the amount of children an object can have? Thanks, Ed. 回答1: Yes it can but until heap out of memory. var a = {}; var i = 0; while(true){ a[i] = null;

问题 This question already has answers here : Are there limits to the number of properties in a JavaScript object? (6 answers) Closed 8 days ago . I'm aware that the ECMA script spec says that an object can have infinite children however I also understand many ECMA script implementations do not conform to this. I was wondering if node has a limit on the amount of children an object can have? Thanks, Ed. 回答1: Yes it can but until heap out of memory. var a = {}; var i = 0; while(true){ a[i] = null;

问题 The JVM spec states that references only take up one local variable slot( jvms12 2.6.1). Additionally it states that double and long , take up two local variable slots because they are 64-bit. Does this mean that all JVM compliant implementations must use 32-bit addressing? How do 64-bit JVMs handle this? Do they use 64 bit local variable slots, or do they use 2 slots for references? 回答1: Does this mean that all JVM compliant implementations must use 32-bit addressing? How do 64-bit JVMs

问题 The JVM spec states that references only take up one local variable slot( jvms12 2.6.1). Additionally it states that double and long , take up two local variable slots because they are 64-bit. Does this mean that all JVM compliant implementations must use 32-bit addressing? How do 64-bit JVMs handle this? Do they use 64 bit local variable slots, or do they use 2 slots for references? 回答1: Does this mean that all JVM compliant implementations must use 32-bit addressing? How do 64-bit JVMs

问题 The JVM spec states that references only take up one local variable slot( jvms12 2.6.1). Additionally it states that double and long , take up two local variable slots because they are 64-bit. Does this mean that all JVM compliant implementations must use 32-bit addressing? How do 64-bit JVMs handle this? Do they use 64 bit local variable slots, or do they use 2 slots for references? 回答1: Does this mean that all JVM compliant implementations must use 32-bit addressing? How do 64-bit JVMs

问题 What does the minus sign mean? [14] CharData ::= [^<&]* - ([^<&]* ']]>' [^<&]*) From the w3c XML 1.0 specification Also, where can I find information related to the syntax grammar? I'm having troubling finding the specification about the specification, if that makes any sense. 回答1: Minus ( - ) is part of the Extended Backus-Naur Form (EBNF) notation used by the W3C XML Recommendation to define the formal grammar of XML: Minus ( - ) in A - B matches any string that matches A but does not match