P4::UnparsedConstant Struct Reference

#include <constantParsing.h>

Public Member Functions
void	toJSON (JSONGenerator &) const
	If true, a bitwidth and separator are present.

Static Public Member Functions
static UnparsedConstant	fromJSON (JSONLoader &)

Public Attributes
unsigned	base
	An ignored prefix of the numeric constant (e.g. '0x').
bool	hasWidth
	The base in which the constant is expressed.
unsigned	skip
	Raw P4 text which was recognized as a numeric constant.
cstring	text

Detailed Description

An unparsed numeric constant. We produce these as token values during lexing. The parser is responsible for actually interpreting the raw text as a numeric value and transforming it into an IR::Constant using parseConstant().

To illustrate how a numeric constant is represented using this struct, here is a breakdown of '16w0x12':

     ___
    /                                    ___
    |                                   /
    |   bitwidth (if @hasWidth)        |       16
    |                                   \___
    |
    |                                    ___
    |                                   /
    |   separator (if @hasWidth)       |       w
    |                                   \___

@text | | ___ | / | ignored prefix of length

| ___ | | ___ | / | numeric value in base @base | w | ___ ___

Simple numeric constants like '5' are specified by setting @hasWidth to false and providing a