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pinojs · Aug 1, 2020 · 88e6602 · 88e6602
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diff --git a/docs/api.md b/docs/api.md
@@ -470,7 +470,7 @@ logger.info({MIX: {IN: true}})
 // {"level":30,"time":1531254555820,"pid":55956,"hostname":"x","MIX":{"IN":true}}
 ```
 
-<a id=message></a>
+<a id="message"></a>
 #### `message` (String)
 
 A `message` string can optionally be supplied as the first parameter, or
@@ -488,6 +488,8 @@ The `message` parameter takes precedence over the `mergedObject`.
 That is, if a `mergedObject` contains a `msg` property, and a `message` parameter
 is supplied in addition, the `msg` property in the output log will be the value of
 the `message` parameter not the value of the `msg` property on the `mergedObject`.
+See [Avoid Message Conflict](./help.md#avoid-message-conflict) for information
+on how to overcome this limitation.
 
 The `messageKey` option can be used at instantiation time to change the namespace
 from `msg` to another string as preferred.
@@ -505,7 +507,7 @@ then be interpolated accordingly.
 * See [`messageKey` pino option](#opt-messagekey)
 * See [`...interpolationValues` log method parameter](#interpolationvalues)
 
-<a id=interpolationvalues></a>
+<a id="interpolationvalues"></a>
 #### `...interpolationValues` (Any)
 
 All arguments supplied after `message` are serialized and interpolated according

diff --git a/docs/help.md b/docs/help.md
@@ -12,6 +12,7 @@
 * [Pino with `debug`](#debug)
 * [Unicode and Windows terminal](#windows)
 * [Mapping Pino Log Levels to Google Cloud Logging (Stackdriver) Serverity Levels](#stackdriver)
+* [Avoid Message Conflict](#avoid-message-conflict)
 
 <a id="exit-logging"></a>
 ## Exit logging
@@ -282,3 +283,34 @@ module.exports = function createLogger(options) {
   return pino(Object.assign({}, options, defaultPinoConf))
 }
 ```
+
+<a id="avoid-message-conflict"></a>
+## Avoid Message Conflict
+
+As described in the [`message` documentation](./api.md#message), when a log
+is written like `log.info({ msg: 'a message' }, 'another message')` then the
+final output JSON will have `"msg":"another message"` and the `'a message'`
+string will be lost. To overcome this, the [`logMethod` hook](./api.md#logmethod)
+can be used:
+
+```js
+'use strict'
+
+const log = require('pino')({
+  level: 'debug',
+  hooks: {
+    logMethod (inputArgs, method) {
+      if (inputArgs.length === 2 && inputArgs[0].msg) {
+       inputArgs[0].originalMsg = inputArgs[0].msg
+      }
+      return method.apply(this, inputArgs)
+    }
+  }
+})
+
+log.info('no original message')
+log.info({ msg: 'mapped to originalMsg' }, 'a message')
+
+// {"level":30,"time":1596313323106,"pid":63739,"hostname":"foo","msg":"no original message"}
+// {"level":30,"time":1596313323107,"pid":63739,"hostname":"foo","msg":"a message","originalMsg":"mapped to originalMsg"}
+```