Basic Examples (4) 

Change which symbol a message is issued from:

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Compare to the normal message:

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Replace message tags:

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Replace using patterns:

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Replace using a list of rules:

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Scope (7) 

Specify a replacement function:

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Named replacement functions (3) 

Replace only the message symbol:

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Replace only the message tag:

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Replace only in message parameters:

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Automatic replacement function (4) 

When the replacement function is Automatic, the type of replacement differs depending on the rules given. Here are some test messages:

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Symbol replacements change the message symbol (first argument of MessageName):

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String replacements change the message tag (second argument of MessageName):

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Mixing rules results in replacement across the whole message (including parameters):

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Applications (1) 

Define a function that takes ownership of messages issued:

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Properties and Relations (2) 

See the expression structure that's passed to the replacement function:

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If the target symbol and tag is not a defined message, it will be defined temporarily in order to print the message:

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The temporary message definition is cleared:

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If the message is already defined for the target symbol and tag, it won't be changed:

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Possible Issues (2) 

Changing the target message template can result in additional errors if the number of template slots increases:

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Compare to the original:

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If the number of template slots decreases, some parameters will be dropped:

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Compare to the original:

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The original message is never issued, so inner code that checks for specific messages may give unexpected results:

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MessageReplace does not affect quieted messages, so the underlying code will work as expected:

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Neat Examples (2) 

Replace numbers in messages using IntegerName:

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Use replacement rules to temporarily define alternate behavior for messages:

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