SequenceOf type

class pyasn1.type.univ.SequenceOf(componentType=None, tagSet=TagSet(), subtypeSpec=ConstraintsIntersection(), sizeSpec=ConstraintsIntersection())

Create SequenceOf type.

SequenceOf objects are mutable and duck-type Python list objects.

Parameters:
  • componentType (PyAsn1Item derivative) – A pyasn1 object representing ASN.1 type allowed within SequenceOf type
  • tagSet (TagSet) – Object representing non-default ASN.1 tag(s)
  • subtypeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 subtype constraint(s)
  • sizeSpec (ConstraintsIntersection) – Object representing collection size constraint

Note

The SequenceOf type models a collection of elements of a single ASN.1 type. Ordering of the components is preserved upon de/serialization.

clone(componentType=None, tagSet=TagSet(), subtypeSpec=ConstraintsIntersection())

Create a copy of a SequenceOf type or object.

Any parameters to the clone() method will replace corresponding properties of the SequenceOf object.

Parameters:
  • tagSet (TagSet) – Object representing non-default ASN.1 tag(s)
  • subtypeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 subtype constraint(s)
  • sizeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 size constraint(s)
Returns:

new instance of SequenceOf type/value

subtype(componentType=None, implicitTag=Tag(), explicitTag=Tag(), subtypeSpec=ConstraintsIntersection())

Create a copy of a SequenceOf type or object.

Any parameters to the subtype() method will be added to the corresponding properties of the SequenceOf object.

Parameters:
  • tagSet (TagSet) – Object representing non-default ASN.1 tag(s)
  • subtypeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 subtype constraint(s)
  • sizeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 size constraint(s)
Returns:

new instance of SequenceOf type/value

tagSet = TagSet((), Tag(tagClass=0, tagFormat=32, tagId=16))

Set (on class, not on instance) or return a TagSet object representing ASN.1 tag(s) associated with SequenceOf type.

componentType = None

Default PyAsn1Item derivative object representing ASN.1 type allowed within SequenceOf type

subtypeSpec = ConstraintsIntersection()

Set (on class, not on instance) or return a ConstraintsIntersection object imposing constraints on SequenceOf type initialization values.

sizeSpec = ConstraintsIntersection()

Default ConstraintsIntersection object imposing size constraint on SequenceOf objects

effectiveTagSet

For SequenceOf type is equivalent to tagSet

getComponentByPosition(idx)

Return SequenceOf type component value by position.

Equivalent to Python sequence subscription operation (e.g. []).

Parameters:idx (int) – Component index (zero-based). Must either refer to an existing component or to N+1 component (if componentType is set). In the latter case a new component type gets instantiated and appended to the SequenceOf sequence.
Returns:PyAsn1Item – a pyasn1 object
isSameTypeWith(other, matchTags=True, matchConstraints=True)

Examine SequenceOf type for equality with other ASN.1 type.

ASN.1 tags (tag) and constraints (constraint) are examined when carrying out ASN.1 types comparison.

No Python inheritance relationship between PyASN1 objects is considered.

Parameters:other (a pyasn1 type object) – Class instance representing ASN.1 type.
Returns:boolTrue if other is SequenceOf type, False otherwise.
isSuperTypeOf(other, matchTags=True, matchConstraints=True)

Examine SequenceOf type for subtype relationship with other ASN.1 type.

ASN.1 tags (tag) and constraints (constraint) are examined when carrying out ASN.1 types comparison.

No Python inheritance relationship between PyASN1 objects is considered.

Parameters:other (a pyasn1 type object) – Class instance representing ASN.1 type.
Returns:boolTrue if other is a subtype of SequenceOf type, False otherwise.
isValue

Indicate if SequenceOf object represents ASN.1 type or ASN.1 value.

In other words, if isValue is True, then the ASN.1 object is initialized.

For the purpose of this check, empty SequenceOf object is considered as initialized.

Returns:boolTrue if object represents ASN.1 value and type, False if object represents just ASN.1 type.

Note

There is an important distinction between PyASN1 type and value objects. The PyASN1 type objects can only participate in ASN.1 type operations (subtyping, comparison etc) and serve as a blueprint for serialization codecs to resolve ambiguous types.

The PyASN1 value objects can additionally participate in most of built-in Python operations.

setComponentByPosition(idx, value=NoValue(), verifyConstraints=True, matchTags=True, matchConstraints=True)

Assign SequenceOf type component by position.

Equivalent to Python sequence item assignment operation (e.g. []) or list.append() (when idx == len(self)).

Parameters:
  • idx (int) – Component index (zero-based). Must either refer to existing component or to N+1 component. In the latter case a new component type gets instantiated (if componentType is set, or given ASN.1 object is taken otherwise) and appended to the SequenceOf sequence.
  • value (object or PyAsn1Item derivative) – A Python value to initialize SequenceOf component with (if componentType is set) or ASN.1 value object to assign to SequenceOf component.
  • verifyConstraints (bool) – If False, skip constraints validation
  • matchTags (bool) – If False, skip component tags matching
  • matchConstraints (bool) – If False, skip component constraints matching
Returns:

self

Raises:

IndexError: – When idx > len(self)

tagMap

Return a TagMap object mapping ASN.1 tags to ASN.1 objects within callee object.