Tangram's persistent type system is extensible, allowing you to mount your own types and make them
persistent. All you have to do is to register your type and provide mapping code. See
Tangram::Type::Extending.
Tangram comes with built-in support for the following types:
SimpleScalartypes
Supported are strings, integers, real numbers and dates. More types of this ilk are easily added.
"string", "int", "real": see Tangram::Type::Scalar
"date", "time", "datetime", "dmdatetime": see "Date/Type/Date/DateTime" in Tangram::Type
CompoundStructuretypes
"perl_dump": see Tangram::Type::Dump::Perl. A "perl_dump" structure may contain any structure which
Data::Dumper can dump successfully.
"storable": see Tangram::Type::Dump::Storable. Very much like "perl_dump", but implemented via the
`Storable' serialisation engine.
"yaml": see Tangram::Type::Dump::YAML. Very much like "perl_dump", but implemented via the `YAML'
serialisation engine. Doesn't currently work, due to inadequacies in the current Perl YAML
implementation.
NEWinTangram2.08:
"idbif": see Tangram::Type::Dump::Any. Like the above, but can combine multiple object properties
into a single database column.
`Flat'Array&Hashtypes
Note: these are only actually required if you need to be able to query on individual fields inside
the array/hash - otherwise, the "perl_dump" or "idbif" mapping is a lot faster and more flexible.
"flat_array": see "Array/Scalar" in Tangram::Type
"flat_hash": see "Hash/Scalar" in Tangram::Type
Referencestootherobjects
"ref": see Tangram::Type::Ref::FromMany (implementing an Nto1 relationship, in which any object can
be the referant)
Setsofotherobjects
Set relationships are closest to the main type of relationship used in an RDBMS. Avid CompSci
students will know that the relational database model is based heavily on `Set Theory', which is a
subset of a more general concept of `Categories' - generic couplings of a number of classes.
In Perl space, these collections are represented via the Set::Object module. Sets may not have
duplicate elements, and cannot contain undef values.
"set": see Tangram::Type::Set::FromMany (implementing an unorderedNtoN relationship, with all
objects sharing a common base class)
"iset": see Tangram::Type::Set::FromOne (implementing an unordered1toN relationship, with all
objects sharing a common base class)
Arraysofotherobjects
The addition to Sets, you can have `Arrays' of objects, represented by a standard Perl array in
memory. Arrays may contain undef values (in the middle of the list), and the "array" type may
contain duplicates (ie, the same element present in separate places in the list).
"array" : see Tangram::Type::Array::FromMany (implementing an orderedNtoN relationship, with all
objects sharing a common base class)
"iarray": see Tangram::Type::Array::FromOne (implementing an ordered1toN relationship, with all
objects sharing a common base class)
Hashesofotherobjects
Much like the Array types, the Hash types are indexed via a string value, and represented as a Perl
hash in memory. These hashes may not contain undef values (those are dropped). The "hash" type may
contain duplicate elements.
"hash" : see Tangram::Type::Hash::FromMany (implementing a keyedNtoN relationship, with all
objects sharing a common base class)
"ihash": see Tangram::Type::Hash::FromOne (implementing a keyed1toN relationship, with all objects
sharing a common base class)
perl v5.36.0 2022-10-16 Tangram::Type(3pm)