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Preserves Path
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Preserves Schema
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< h1 id = "overview" > Overview< / h1 >
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< div class = "highlight" > < pre > < span > < / span > < code > pip< span class = "w" > < / span > install< span class = "w" > < / span > preserves
< / code > < / pre > < / div >
< p > This package (< a href = "https://pypi.org/project/preserves/" > < code > preserves< / code > on pypi.org< / a > ) implements
< a href = "https://preserves.dev/" > Preserves< / a > for Python 3.x. It provides the core < a href = "https://preserves.dev/preserves.html#semantics" > semantics< / a > as well
as both the < a href = "https://preserves.dev/preserves-text.html" > human-readable text syntax< / a > (a superset
of JSON) and < a href = "https://preserves.dev/preserves-binary.html" > machine-oriented binary format< / a >
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(including < a href = "https://preserves.dev/canonical-binary.html" > canonicalization< / a > ) for Preserves. It
also implements < a href = "https://preserves.dev/preserves-schema.html" > Preserves Schema< / a > and < a href = "https://preserves.dev/preserves-path.html" > Preserves
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Path< / a > .< / p >
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< li > Main package API: < a href = "api" > preserves< / a > < / li >
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< h2 id = "what-is-preserves" > What is Preserves?< / h2 >
< p > < em > Preserves< / em > is a data model, with associated serialization formats.< / p >
< p > It supports < em > records< / em > with user-defined < em > labels< / em > , embedded
< em > references< / em > , and the usual suite of atomic and compound data types,
including < em > binary< / em > data as a distinct type from text strings. Its
< em > annotations< / em > allow separation of data from metadata such as comments,
trace information, and provenance information.< / p >
< p > Preserves departs from many other data languages in defining how to
< em > compare< / em > two values. Comparison is based on the data model, not on
syntax or on data structures of any particular implementation
language.< / p >
< h2 id = "mapping-between-preserves-values-and-python-values" > Mapping between Preserves values and Python values< / h2 >
< p > Preserves < code > Value< / code > s are categorized in the following way:< / p >
< div class = "highlight" > < pre > < span > < / span > < code > Value = Atom
| Compound
| Embedded
Atom = Boolean
| Float
| Double
| SignedInteger
| String
| ByteString
| Symbol
Compound = Record
| Sequence
| Set
| Dictionary
< / code > < / pre > < / div >
< p > Python's strings, byte strings, integers, booleans, and double-precision floats stand directly
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for their Preserves counterparts. Wrapper objects for < a class = "autorefs autorefs-internal" href = "values/#preserves.values.Float" > Float< / a > and
< a class = "autorefs autorefs-internal" href = "values/#preserves.values.Symbol" > Symbol< / a > complete the suite of atomic types.< / p >
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< p > Python's lists and tuples correspond to Preserves < code > Sequence< / code > s, and dicts and sets to
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< code > Dictionary< / code > and < code > Set< / code > values, respectively. Preserves < code > Record< / code > s are represented by
< a class = "autorefs autorefs-internal" href = "values/#preserves.values.Record" > Record< / a > objects. Finally, embedded values are represented by
< a class = "autorefs autorefs-internal" href = "values/#preserves.values.Embedded" > Embedded< / a > objects.< / p >
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