blocks|key|976734|text|显而易见的答案是这样的：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|976735|var+origCall+=+Function.prototype.call;
Function.prototype.call+=+function+(thisArg)+{
++++console.log("calling+a+function");

++++var+args+=+Array.prototype.slice.call(arguments,+1);
++++origCall.apply(thisArg,+args);
};|code-block|syntax|javascript|976736|但这实际上立即进入了无限循环，因为调用console.log的行为执行了一个函数调用，它调用了console.log，它执行了一个函数调用，它调用了console.log，它...|offset|length|style|CODE|976737|重点是，我不确定这是不可能的。|976738|entityMap^0|0|0|J|B|1B|B|22|B|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]|$I|V|J|W|K|L]|$I|X|J|Y|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|Z|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|10|8|@]|9|@]|A|$]]]|P|$]]

The obvious answer is something like the following:

<pre><code>var origCall = Function.prototype.call;
Function.prototype.call = function (thisArg) {
 console.log("calling a function");

 var args = Array.prototype.slice.call(arguments, 1);
 origCall.apply(thisArg, args);
};
</code></pre>

But this actually immediately enters an infinite loop, because the very act of calling <code>console.log</code> executes a function call, which calls <code>console.log</code>, which executes a function call, which calls <code>console.log</code>, which...

Point being, I'm not sure this is possible.

blocks|key|976801|text|我得到了一些结果，并且没有页面崩溃，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|976802|(function+()+{
++var+
++++origCall+=+Function.prototype.call,
++++log+=+document.getElementById+('call_log');++

++//+Override+call+only+if+call_log+element+is+present++++
++log+&&+(Function.prototype.call+=+function+(self)+{
++++var+r+=+(typeof+self+===+'string'+?+'"'+%2B+self+%2B+'"'+:+self)+%2B+'.'+%2B+this+%2B+'+(';+
++++for+(var+i+=+1;+i+<+arguments.length;+i%2B%2B)+r+%2B=+(i+>+1+?+',+'+:+'')+%2B+arguments[i];++
++++log.innerHTML+%2B=+r+%2B+') ';



++++this.apply+(self,+Array.prototype.slice.apply+(arguments,+[1]));
++});
})+();|code-block|syntax|javascript|976803|仅在Chrome版本9.xxx中测试。|976804|它当然没有记录所有的函数调用，但它记录了一些函数调用！我怀疑只有对自己的“call”实际调用才会被处理|976805|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I am getting SOME results and no page crashes with the following : 

<pre><code>(function () {
 var 
 origCall = Function.prototype.call,
 log = document.getElementById ('call_log'); 

 // Override call only if call_log element is present 
 log &amp;&amp; (Function.prototype.call = function (self) {
 var r = (typeof self === 'string' ? '"' + self + '"' : self) + '.' + this + ' ('; 
 for (var i = 1; i &lt; arguments.length; i++) r += (i &gt; 1 ? ', ' : '') + arguments[i]; 
 log.innerHTML += r + ')&lt;br/&gt;';



 this.apply (self, Array.prototype.slice.apply (arguments, [1]));
 });
}) ();
</code></pre>

Only tested in Chrome version 9.xxx.

It is certainly not logging all function calls, but it is logging some! 
I suspect only actual calls to 'call' intself are being processed

blocks|key|761329|text|只是一个快速的测试，但它似乎对我很有效。这种方式可能没有用，但我基本上是在替换的时候恢复原型，然后在退出之前“恢复”它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|761330|这个例子简单地记录了所有的函数调用-尽管可能有一些致命的缺陷我还没有检测到；在喝咖啡休息的时候做这件事|761331|实现|761332|callLog+=+[];

/*+set+up+an+override+for+the+Function+call+prototype
+*+@param+func+the+new+function+wrapper
+*/
function+registerOverride(func)+{
+++oldCall+=+Function.prototype.call;
+++Function.prototype.call+=+func;
}

/*+restore+you+to+your+regular+programming+
+*/
function+removeOverride()+{
+++Function.prototype.call+=+oldCall;
}

/*+a+simple+example+override
+*+nb:+if+you+use+this+from+the+node.js+REPL+you'll+get+a+lot+of+buffer+spam
+*+++++as+every+keypress+is+processed+through+a+function
+*+Any+useful+logging+would+ideally+compact+these+calls
+*/
function+myCall()+{+
+++//+first+restore+the+normal+call+functionality
+++Function.prototype.call+=+oldCall;

+++//+gather+the+data+we+wish+to+log
+++var+entry+=+{this:this,+name:this.name,+args:{}};
+++for+(var+key+in+arguments)+{
+++++if+(arguments.hasOwnProperty(key))+{
++++++entry.args[key]+=+arguments[key];
+++++}
+++}
+++callLog.push(entry);

+++//+call+the+original+(I+may+be+doing+this+part+naughtily,+not+a+js+guru)
+++this(arguments);

+++//+put+our+override+back+in+power
+++Function.prototype.call+=+myCall;
}|code-block|syntax|javascript|761333|用法|761334|我遇到了一些问题，包括在一个大粘贴中调用它，所以为了测试上面的函数，我在REPL中输入了以下内容：|761335|/*+example+usage
+*+(only+tested+through+the+node.js+REPL)
+*/
registerOverride(myCall);
console.log("hello,+world!");
removeOverride(myCall);
console.log(callLog);|761336|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|U|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|V|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|X|8|@]|9|@]|A|$]]|$1|O|3|P|5|H|7|Y|8|@]|9|@]|A|$I|J]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

Only a quick test, but it seems to work for me.
It may not be useful this way, but I'm basically restoring the prototype whilst in my replacement's body and then "unrestoring" it before exiting.

This example simply logs all function calls - though there may be some fatal flaw I've yet to detect; doing this over a coffee break

<h2>implementation</h2>

<pre><code>callLog = [];

/* set up an override for the Function call prototype
 * @param func the new function wrapper
 */
function registerOverride(func) {
 oldCall = Function.prototype.call;
 Function.prototype.call = func;
}

/* restore you to your regular programming 
 */
function removeOverride() {
 Function.prototype.call = oldCall;
}

/* a simple example override
 * nb: if you use this from the node.js REPL you'll get a lot of buffer spam
 * as every keypress is processed through a function
 * Any useful logging would ideally compact these calls
 */
function myCall() { 
 // first restore the normal call functionality
 Function.prototype.call = oldCall;

 // gather the data we wish to log
 var entry = {this:this, name:this.name, args:{}};
 for (var key in arguments) {
 if (arguments.hasOwnProperty(key)) {
 entry.args[key] = arguments[key];
 }
 }
 callLog.push(entry);

 // call the original (I may be doing this part naughtily, not a js guru)
 this(arguments);

 // put our override back in power
 Function.prototype.call = myCall;
}
</code></pre>

<h2>usage</h2>

I've had some issues including calls to this in one big paste, so here's what I was typing into the REPL in order to test the above functions:

<pre><code>/* example usage
 * (only tested through the node.js REPL)
 */
registerOverride(myCall);
console.log("hello, world!");
removeOverride(myCall);
console.log(callLog);
</code></pre>

blocks|key|976902|text|你可以重写Function.prototype.call，只要确保在你的重写中只有apply函数即可。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|976903|window.callLog+=+[];
Function.prototype.call+=+function()+{
++++Array.prototype.push.apply(window.callLog,+[[this,+arguments]]);
++++return+this.apply(arguments[0],+Array.prototype.slice.apply(arguments,[1]));
};|code-block|syntax|javascript|976904|entityMap^0|5|N|15|5|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

You can override <code>Function.prototype.call</code>, just make sure to only <code>apply</code> functions within your override.

<pre><code>window.callLog = [];
Function.prototype.call = function() {
 Array.prototype.push.apply(window.callLog, [[this, arguments]]);
 return this.apply(arguments[0], Array.prototype.slice.apply(arguments,[1]));
};
</code></pre>

blocks|key|976934|text|我发现使用自动过程来检测文件是最容易的。我创建这个小工具是为了让我自己更容易。也许其他人会发现它很有用。它基本上是awk，但对于Javascript程序员来说更容易使用。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|976935|//+This+tool+reads+a+file+and+builds+a+buffer+of+say+ten+lines.++
//+When+a+line+falls+off+the+end+of+the+buffer,+it+gets+written+to+the+output+file.+
//+When+a+line+is+read+from+the+input+file,+it+gets+written+to+the+first+line+of+the+buffer.+
//+After+each+occurrence+of+a+line+being+read+from+the+input+file+and/or+written+to+the+output+
//+file,+a+routine+is+given+control.++The+routine+has+the+option+of+operating+on+the+buffer.++
//+It+can+insert+a+line+before+or+after+a+line+that+is+there,+based+on+the+lines+surrounding.+
//+
//+The+immediate+case+is+that+if+I+have+a+set+of+lines+like+this:+
//+
//+++++++++++++getNum:+function+(a,+c)+{
//+++++++++++++++++console.log(`getNum:+function+(a,+c)+{`);
//+++++++++++++++++console.log(`arguments.callee+=+${arguments.callee.toString().substr(0,100)}`);
//+++++++++++++++++console.log(`arguments.length+=+${arguments.length}`);
//+++++++++++++++++for+(var+i+=+0;+i+<+arguments.length;+i%2B%2B)+{+console.log(`arguments[${i}]+=+${arguments[i]+?+arguments[i].toString().substr(0,100)+:+'falsey'}`);+}
//+++++++++++++++++var+d+=+b.isStrNum(a)+?+(c+&&+b.isString(c)+?+RegExp(c)+:+b.getNumRegx).exec(a)+:+null;
//+++++++++++++++++return+d+?+d[0]+:+null
//+++++++++++++},
//+++++++++++++compareNums:+function+(a,+c,+d)+{
//+++++++++++++++++console.log(`arguments.callee+=+${arguments.callee.toString().substr(0,100)}`);
//+
//+I+want+to+change+that+to+a+set+of+lines+like+this:+
//+
//+++++++++++++getNum:+function+(a,+c)+{
//+++++++++++++++++console.log(`getNum:+function+(a,+c)+{`);
//+++++++++++++++++console.log(`arguments.callee+=+${arguments.callee.toString().substr(0,100)}`);
//+++++++++++++++++console.log(`arguments.length+=+${arguments.length}`);
//+++++++++++++++++for+(var+i+=+0;+i+<+arguments.length;+i%2B%2B)+{+console.log(`arguments[${i}]+=+${arguments[i]+?+arguments[i].toString().substr(0,100)+:+'falsey'}`);+}
//+++++++++++++++++var+d+=+b.isStrNum(a)+?+(c+&&+b.isString(c)+?+RegExp(c)+:+b.getNumRegx).exec(a)+:+null;
//+++++++++++++++++return+d+?+d[0]+:+null
//+++++++++++++},
//+++++++++++++compareNums:+function+(a,+c,+d)+{
//+++++++++++++++++console.log(`compareNums:+function+(a,+c,+d)+{`);
//+++++++++++++++++console.log(`arguments.callee+=+${arguments.callee.toString().substr(0,100)}`);
//+
//+We+are+trying+to+figure+out+how+a+set+of+functions+work,+and+I+want+each+function+to+report+
//+its+name+when+we+enter+it.
//+
//+To+save+time,+options+and+the+function+that+is+called+on+each+cycle+appear+at+the+beginning+
//+of+this+file.++Ideally,+they+would+be+--something+options+on+the+command+line.+


const+readline+=+require('readline');


//------------------------------------------------------------------------------------------------

//+Here+are+the+things+that+would+properly+be+options+on+the+command+line.++Put+here+for+
//+speed+of+building+the+tool.+

const+frameSize+=+10;
const+shouldReportFrame+=+false;

function+reportFrame()+{
++++for+(i+=+frame.length+-+1;+i+>=+0;+i--)+{
++++++++console.error(`${i}.++${frame[i]}`);++//+Using+the+error+stream+because+the+stdout+stream+may+have+been+coopted.+
++++}
}

function+processFrame()+{
++++//+console.log(`********++${frame[0]}`);
++++//+if+(frame[0].search('console.log(\`arguments.callee+=+\$\{arguments.callee.toString().substr(0,100)\}\`);')+!==+-1)+{
++++//+if+(frame[0].search('arguments.callee')+!==+-1)+{
++++//+if+(frame[0].search(/console.log$`arguments.callee+=+\$\{arguments.callee.toString\($.substr$0,100$\}`\);/)+!==+-1)+{
++++var+matchArray+=+frame[0].match(/([+\t]*)console.log$`arguments.callee+=+\$\{arguments.callee.toString\($.substr$0,100$\}`\);/);
++++if+(matchArray)+{
++++++++//+console.log('********++Matched');
++++++++frame.splice(1,+0,+`${matchArray[1]}console.log('${frame[1]}');`);
++++}
}

//------------------------------------------------------------------------------------------------


var+i;
var+frame+=+[];

const+rl+=+readline.createInterface({
++++input:+process.stdin
});

rl.on('line',+line+=>+{
++++if+(frame.length+>+frameSize+-+1)+{
++++++++for+(i+=+frame.length+-+1;+i+>+frameSize+-+2;+i--)+{
++++++++++++process.stdout.write(`${frame[i]}\n`);
++++++++}
++++}
++++frame.splice(frameSize+-+1,+frame.length+-+frameSize+%2B+1);
++++frame.splice(0,+0,+line);
++++if+(shouldReportFrame)+reportFrame();
++++processFrame();
++++//+process.stdout.write(`${line}\n`);++//+readline+gives+us+the+line+with+the+newline+stripped+off
});

rl.on('close',+()+=>+{
++++for+(i+=+frame.length+-+1;+i+>+-1;+i--)+{
++++++++process.stdout.write(`${frame[i]}\n`);
++++}
});


//+Notes
//+
//+We+are+not+going+to+control+the+writing+to+the+output+stream.++In+particular,+we+are+not+
//+going+to+listen+for+drain+events.++Nodejs'+buffering+may+get+overwhelmed.+
//+|code-block|syntax|javascript|976936|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I found it easiest to instrument the file, using an automatic process. I built this little tool to make it easier for myself. Perhaps somebody else will find it useful. It's basically awk, but easier for a Javascript programmer to use. 

<pre><code>// This tool reads a file and builds a buffer of say ten lines. 
// When a line falls off the end of the buffer, it gets written to the output file. 
// When a line is read from the input file, it gets written to the first line of the buffer. 
// After each occurrence of a line being read from the input file and/or written to the output 
// file, a routine is given control. The routine has the option of operating on the buffer. 
// It can insert a line before or after a line that is there, based on the lines surrounding. 
// 
// The immediate case is that if I have a set of lines like this: 
// 
// getNum: function (a, c) {
// console.log(`getNum: function (a, c) {`);
// console.log(`arguments.callee = ${arguments.callee.toString().substr(0,100)}`);
// console.log(`arguments.length = ${arguments.length}`);
// for (var i = 0; i &lt; arguments.length; i++) { console.log(`arguments[${i}] = ${arguments[i] ? arguments[i].toString().substr(0,100) : 'falsey'}`); }
// var d = b.isStrNum(a) ? (c &amp;&amp; b.isString(c) ? RegExp(c) : b.getNumRegx).exec(a) : null;
// return d ? d[0] : null
// },
// compareNums: function (a, c, d) {
// console.log(`arguments.callee = ${arguments.callee.toString().substr(0,100)}`);
// 
// I want to change that to a set of lines like this: 
// 
// getNum: function (a, c) {
// console.log(`getNum: function (a, c) {`);
// console.log(`arguments.callee = ${arguments.callee.toString().substr(0,100)}`);
// console.log(`arguments.length = ${arguments.length}`);
// for (var i = 0; i &lt; arguments.length; i++) { console.log(`arguments[${i}] = ${arguments[i] ? arguments[i].toString().substr(0,100) : 'falsey'}`); }
// var d = b.isStrNum(a) ? (c &amp;&amp; b.isString(c) ? RegExp(c) : b.getNumRegx).exec(a) : null;
// return d ? d[0] : null
// },
// compareNums: function (a, c, d) {
// console.log(`compareNums: function (a, c, d) {`);
// console.log(`arguments.callee = ${arguments.callee.toString().substr(0,100)}`);
// 
// We are trying to figure out how a set of functions work, and I want each function to report 
// its name when we enter it.
// 
// To save time, options and the function that is called on each cycle appear at the beginning 
// of this file. Ideally, they would be --something options on the command line. 


const readline = require('readline');


//------------------------------------------------------------------------------------------------

// Here are the things that would properly be options on the command line. Put here for 
// speed of building the tool. 

const frameSize = 10;
const shouldReportFrame = false;

function reportFrame() {
 for (i = frame.length - 1; i &gt;= 0; i--) {
 console.error(`${i}. ${frame[i]}`); // Using the error stream because the stdout stream may have been coopted. 
 }
}

function processFrame() {
 // console.log(`******** ${frame[0]}`);
 // if (frame[0].search('console.log(\`arguments.callee = \$\{arguments.callee.toString().substr(0,100)\}\`);') !== -1) {
 // if (frame[0].search('arguments.callee') !== -1) {
 // if (frame[0].search(/console.log$`arguments.callee = \$\{arguments.callee.toString\($.substr$0,100$\}`\);/) !== -1) {
 var matchArray = frame[0].match(/([ \t]*)console.log$`arguments.callee = \$\{arguments.callee.toString\($.substr$0,100$\}`\);/);
 if (matchArray) {
 // console.log('******** Matched');
 frame.splice(1, 0, `${matchArray[1]}console.log('${frame[1]}');`);
 }
}

//------------------------------------------------------------------------------------------------


var i;
var frame = [];

const rl = readline.createInterface({
 input: process.stdin
});

rl.on('line', line =&gt; {
 if (frame.length &gt; frameSize - 1) {
 for (i = frame.length - 1; i &gt; frameSize - 2; i--) {
 process.stdout.write(`${frame[i]}\n`);
 }
 }
 frame.splice(frameSize - 1, frame.length - frameSize + 1);
 frame.splice(0, 0, line);
 if (shouldReportFrame) reportFrame();
 processFrame();
 // process.stdout.write(`${line}\n`); // readline gives us the line with the newline stripped off
});

rl.on('close', () =&gt; {
 for (i = frame.length - 1; i &gt; -1; i--) {
 process.stdout.write(`${frame[i]}\n`);
 }
});


// Notes
// 
// We are not going to control the writing to the output stream. In particular, we are not 
// going to listen for drain events. Nodejs' buffering may get overwhelmed. 
// 
</code></pre>

Can I override the behavior of the Function object so that I can inject behavior prior t every function call, and then carry on as normal? Specifically, (though the general idea is intriguing in itself) can I log to the console every function call without having to insert console.log statements everywhere? And then the normal behavior goes on?

I do recognize that this will likely have significant performance problems; I have no intention of having this run typically, even in my development environment. But if it works it seems an elegant solution to get a 1000 meter view on the running code. And I suspect that the answer will show me something deeper about javascript.

Can I override the Javascript Function object to log all function calls?

我是否可以覆盖函数对象的行为，以便可以在每次函数调用之前注入行为，然后像往常一样继续？具体地说，(尽管总体思想本身很有趣)我是否可以将每个函数调用都记录到控制台，而不必到处插入console.log语句？然后正常的行为会继续吗？我确实认识到这可能会有严重的性能问题；我不打算让它典型地运行，即使在我的开发环境中也是如此。...

问我可以重写Javascript函数对象来记录所有函数调用吗？
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问我可以重写Javascript函数对象来记录所有函数调用吗？
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