P4 spec coverage

What P4-16 language spec constructs P4Py currently supports.

P4Py targets v1model and eBPF. The tables below map supported constructs to their spec sections.

Types

Construct	Supported	Spec section	Notes
bit<W>	Yes	§7.1 Base types	Only numeric type
int<W>	No	§7.1 Base types
varbit	No	§7.1 Base types
bool	Yes	§7.1 Base types	Action params, control output
header	Yes	§7.2 Header types	Flat only, all fields bit<W>
Header stacks	No	§7.2 Header types
struct	Yes	§7.2 Header types	Header, bit<W>, and nested struct members
enum	No	§7.3 Other types
typedef	No	§7.3 Other types

Parser

Construct	Supported	Spec section	Notes
Parser declaration	Yes	§13.1 Parser declaration
Named states	Yes	§13.3 Parser states	First state is implicit start
extract()	Yes	§13.4 Data extraction
Unconditional transition	Yes	§13.6 Transition
transition select	Yes	§13.6 Select	Single field, integer or default cases
lookahead	No	§13.4 Data extraction
Sub-parsers	No	§13.1 Parser declaration
Value sets	No	§13.6 Select

Expressions

Construct	Supported	Spec section	Notes
Integer literals	Yes	§8 Expressions	Decimal, hex, width-annotated
Bool literals	Yes	§8 Expressions	true, false
List expressions	Yes	§8 Expressions	For checksum data args
Field access	Yes	§8 Expressions	hdr.ipv4.dstAddr
+, -	Yes	§8 Expressions
Bitwise (&, |, ^, ~)	No	§8 Expressions
Shifts (<<, >>)	No	§8 Expressions
Comparison (==, !=)	No	§8 Expressions	Only in transition select
Slicing	No	§8 Expressions
Concatenation (++)	No	§8 Expressions
Casts	No	§8 Expressions
.isValid()	Yes	§8 Expressions	In control apply blocks only
.setValid()	No	§8 Expressions
.setInvalid()	No	§8 Expressions

Statements

Construct	Supported	Spec section	Notes
Assignment	Yes	§12 Statements
Method call	Yes	§12 Statements	extract, emit
Function call	Yes	§12 Statements	mark_to_drop
if/else	Yes	§12 Statements	Condition must be .isValid()
switch	Yes	§12 Statements	On action_run only
Block statements	No	§12 Statements

Control blocks

Construct	Supported	Spec section	Notes
Control declaration	Yes	§14 Control blocks
Actions	Yes	§14 Control blocks	Direction-less parameters only
Tables	Yes	§14 Control blocks
exact match	Yes	§14 Control blocks
lpm match	Yes	§14 Control blocks
ternary match	No	§14 Control blocks
range match	No	§14 Control blocks
table.apply()	Yes	§14 Control blocks
const entries	Yes	§14 Control blocks

Deparsing

Construct	Supported	Spec section	Notes
Deparser declaration	Yes	§16 Deparsing
emit()	Yes	§16 Deparsing

See also

• v1model coverage for v1model-specific constructs.

• eBPF model coverage for eBPF-specific constructs.