Sequence type

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

Create Sequence type.

Sequence objects are mutable and duck-type Python dict objects.

Parameters:
  • componentType (NamedType) – Object holding named ASN.1 types allowed within this collection
  • 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 Sequence type models a collection of named ASN.1 components. Ordering of the components is preserved upon de/serialization.

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

Create a copy of a Sequence type or object.

Any parameters to the clone() method will replace corresponding properties of the Sequence 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 Sequence type/value
subtype(componentType=None, implicitTag=Tag(), explicitTag=Tag(), subtypeSpec=ConstraintsIntersection())

Create a copy of a Sequence type or object.

Any parameters to the subtype() method will be added to the corresponding properties of the Sequence 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 Sequence type/value
tagSet = TagSet((), Tag(tagClass=0, tagFormat=32, tagId=16))

Default TagSet object for Sequence objects

subtypeSpec = ConstraintsIntersection()

Default ConstraintsIntersection object imposing constraints on Sequence objects

sizeSpec = ConstraintsIntersection()

Default ConstraintsIntersection object imposing constraints on Sequence objects

componentType = NamedTypes()

Default collection of ASN.1 types of component (e.g. NamedType) object imposing size constraint on Sequence objects

getComponentByName(name)

Returns Sequence type component by name.

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

Parameters:name (str) – Sequence type component name
Returns:PyAsn1Item – a pyasn1 object
getComponentByPosition(idx)

Returns Sequence type component by index.

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

Parameters:idx (int) – component index (zero-based)
Returns:PyAsn1Item – a PyASN1 object
isSameTypeWith(other, matchTags=True, matchConstraints=True)

Examine Sequence 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:bool – True if other is Sequence type, False otherwise.
isSuperTypeOf(other, matchTags=True, matchConstraints=True)

Examine Sequence 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:bool – True if other is a subtype of Sequence type, False otherwise.
setComponentByName(name, value=NoValue(), verifyConstraints=True, matchTags=True, matchConstraints=True)

Assign Sequence type component by name.

Equivalent to Python dict item assignment operation (e.g. []).

Parameters:
  • name (str) – Sequence type component name
  • value (object or PyAsn1Item derivative) – A Python or pyasn1 object to assign
  • 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
setComponentByPosition(idx, value=NoValue(), verifyConstraints=True, matchTags=True, matchConstraints=True)

Assign Sequence type component by position.

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

Parameters:
  • idx (int) – Sequence type component index (zero-based)
  • value (object or PyAsn1Item derivative) – A Python or pyasn1 object to assign
  • 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
setDefaultComponents()

Assign default values to all defaulted Sequence type components.

Returns:self