Examples: Strings (of course!), XML, S-expressions, Python pickle files, etc.
What is a data serialization format?
When computers store data in memory, it can be hard to tell what is what:
However, every once in a while it is necessary to transmit some piece of data somewhere else, and then the in-memory format usually is no good. Instead one has to serialize the data so that it can be transmitted (written to a file, written to a socket, etc.).
Serialization is one of the strengths of the Everything Is A String axiom, since it implies that anything that can be stored in a Tcl_Obj has a string representation that Tcl takes care of generating for you, and will automatically parse whenever you need the value back. This may however be regarded as a low-level serialization format, as it is just a dump of the program-internal format in which the data are stored.
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