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Make console logging function configurable.
Split log() into 2 methods: formatArgs() and log(), allowing log to be overridden on a per-namespace or global level. Global log settings trump per-namespace settings.
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‎Readme.md‎

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@@ -96,6 +96,32 @@ setInterval(function(){
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![](https://cloud.githubusercontent.com/assets/71256/3139768/b98c5fd8-e8ef-11e3-862a-f7253b6f47c6.png)
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### stderr vs stdout
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You can set an alternative logging method per-namespace by overriding the `log` method on a per-namespace or globally:
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Example _stderr.js_:
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```js
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var debug = require('../');
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var log = debug('app:log');
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// by default console.log is used
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log('goes to stdout!');
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var error = debug('app:error');
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// set this namespace to log via console.error
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error.log = console.error.bind(console); // don't forget to bind to console!
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error('goes to stderr');
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log('still goes to stdout!');
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// set all output to go via console.warn
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// overrides all per-namespace log settings
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debug.log = console.warn.bind(console);
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log('now goes to stderr via console.warn');
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error('still goes to stderr, but via console.warn now');
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```
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## Authors
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- TJ Holowaychuk

‎browser.js‎

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@@ -7,6 +7,7 @@
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exports = module.exports = require('./debug');
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exports.log = log;
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exports.formatArgs = formatArgs;
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exports.save = save;
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exports.load = load;
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exports.useColors = useColors;
@@ -47,14 +48,14 @@ exports.formatters.j = function(v) {
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return JSON.stringify(v);
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};
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/**
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* Invokes `console.log()` when available.
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* No-op when `console.log` is not a "function".
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* Colorize log arguments if enabled.
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*
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* @api public
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*/
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function log() {
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function formatArgs() {
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var args = arguments;
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var useColors = this.useColors;
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@@ -65,33 +66,43 @@ function log() {
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+ (useColors ? '%c ' : ' ')
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+ '+' + exports.humanize(this.diff);
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if (useColors) {
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var c = 'color: ' + this.color;
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args = [args[0], c, ''].concat(Array.prototype.slice.call(args, 1));
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// the final "%c" is somewhat tricky, because there could be other
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// arguments passed either before or after the %c, so we need to
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// figure out the correct index to insert the CSS into
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var index = 0;
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var lastC = 0;
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args[0].replace(/%[a-z%]/g, function(match) {
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if ('%%' === match) return;
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index++;
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if ('%c' === match) {
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// we only are interested in the *last* %c
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// (the user may have provided their own)
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lastC = index;
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}
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});
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args.splice(lastC, 0, c);
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}
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if (!useColors) return args
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var c = 'color: ' + this.color;
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args = [args[0], c, ''].concat(Array.prototype.slice.call(args, 1));
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// the final "%c" is somewhat tricky, because there could be other
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// arguments passed either before or after the %c, so we need to
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// figure out the correct index to insert the CSS into
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var index = 0;
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var lastC = 0;
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args[0].replace(/%[a-z%]/g, function(match) {
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if ('%%' === match) return;
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index++;
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if ('%c' === match) {
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// we only are interested in the *last* %c
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// (the user may have provided their own)
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lastC = index;
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}
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});
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args.splice(lastC, 0, c);
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return args;
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}
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/**
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* Invokes `console.log()` when available.
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* No-op when `console.log` is not a "function".
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*
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* @api public
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*/
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function log() {
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// This hackery is required for IE8,
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// where the `console.log` function doesn't have 'apply'
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return 'object' == typeof console
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&& 'function' == typeof console.log
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&& Function.prototype.apply.call(console.log, console, args);
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&& Function.prototype.apply.call(console.log, console, arguments);
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}
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/**

‎debug.js‎

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@@ -110,7 +110,11 @@ function debug(namespace) {
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return match;
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});
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exports.log.apply(self, args);
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if ('function' === typeof exports.formatArgs) {
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args = exports.formatArgs.apply(self, args);
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}
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var logFn = exports.log || enabled.log || console.log.bind(console);
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logFn.apply(self, args);
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}
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enabled.enabled = true;
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‎dist/debug.js‎

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@@ -8,6 +8,7 @@
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exports = module.exports = _dereq_('./debug');
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exports.log = log;
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exports.formatArgs = formatArgs;
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exports.save = save;
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exports.load = load;
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exports.useColors = useColors;
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return JSON.stringify(v);
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};
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/**
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* Invokes `console.log()` when available.
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* No-op when `console.log` is not a "function".
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* Colorize log arguments if enabled.
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*
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* @api public
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*/
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function log() {
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function formatArgs() {
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var args = arguments;
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var useColors = this.useColors;
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@@ -66,33 +67,43 @@ function log() {
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+ (useColors ? '%c ' : ' ')
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+ '+' + exports.humanize(this.diff);
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if (useColors) {
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var c = 'color: ' + this.color;
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args = [args[0], c, ''].concat(Array.prototype.slice.call(args, 1));
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if (!useColors) return args
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var c = 'color: ' + this.color;
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args = [args[0], c, ''].concat(Array.prototype.slice.call(args, 1));
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// the final "%c" is somewhat tricky, because there could be other
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// arguments passed either before or after the %c, so we need to
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// figure out the correct index to insert the CSS into
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var index = 0;
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var lastC = 0;
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args[0].replace(/%[a-z%]/g, function(match) {
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if ('%%' === match) return;
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index++;
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if ('%c' === match) {
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// we only are interested in the *last* %c
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// (the user may have provided their own)
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lastC = index;
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}
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});
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// the final "%c" is somewhat tricky, because there could be other
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// arguments passed either before or after the %c, so we need to
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// figure out the correct index to insert the CSS into
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var index = 0;
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var lastC = 0;
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args[0].replace(/%[a-z%]/g, function(match) {
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if ('%%' === match) return;
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index++;
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if ('%c' === match) {
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// we only are interested in the *last* %c
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// (the user may have provided their own)
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lastC = index;
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}
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});
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args.splice(lastC, 0, c);
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return args;
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}
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args.splice(lastC, 0, c);
89-
}
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/**
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* Invokes `console.log()` when available.
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* No-op when `console.log` is not a "function".
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*
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* @api public
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*/
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function log() {
91102
// This hackery is required for IE8,
92103
// where the `console.log` function doesn't have 'apply'
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return 'object' == typeof console
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&& 'function' == typeof console.log
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&& Function.prototype.apply.call(console.log, console, args);
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&& Function.prototype.apply.call(console.log, console, arguments);
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}
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/**
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return match;
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});
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exports.log.apply(self, args);
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if ('function' === typeof exports.formatArgs) {
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args = exports.formatArgs.apply(self, args);
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}
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var logFn = exports.log || enabled.log || console.log.bind(console);
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logFn.apply(self, args);
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}
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enabled.enabled = true;
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‎example/browser.html‎

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var a = debug('worker:a');
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var b = debug('worker:b');
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// set all output to go via console.info
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// instead of console.log
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debug.log = console.info.bind(console);
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setInterval(function(){
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a('doing some work');
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}, 1000);

‎example/stderr.js‎

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var debug = require('../');
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var log = debug('app:log');
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// by default console.log is used
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log('goes to stdout!');
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var error = debug('app:error');
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// set this namespace to log via console.error
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error.log = console.error.bind(console); // don't forget to bind to console!
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error('goes to stderr');
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log('still goes to stdout!');
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// set all output to go via console.warn
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// overrides all per-namespace log settings
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debug.log = console.warn.bind(console);
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log('now goes to stderr via console.warn');
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error('still goes to stderr, but via console.warn now');

‎node.js‎

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@@ -14,6 +14,7 @@ var util = require('util');
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exports = module.exports = require('./debug');
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exports.log = log;
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exports.formatArgs = formatArgs;
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exports.save = save;
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exports.load = load;
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exports.useColors = useColors;
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};
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/**
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* Invokes `console.log()` with the specified arguments,
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* after adding ANSI color escape codes if enabled.
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* Adds ANSI color escape codes if enabled.
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*
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* @api public
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*/
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function log() {
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function formatArgs() {
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var args = arguments;
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var useColors = this.useColors;
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var name = this.namespace;
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args[0] = new Date().toUTCString()
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+ ' ' + name + ' ' + args[0];
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}
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return args;
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}
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/**
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* Invokes `console.log()` with the specified arguments.
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*/
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console.log.apply(console, args);
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function log() {
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return console.log.apply(console, arguments);
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}
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/**

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