a11::flow::Symbol Struct Reference

One name, what it is, and what became of it. More...

#include <cpp/a11/flow/resolve.h>

Public Attributes
SymbolKind	kind = SymbolKind::kInputPort
std::string	name
syntax::Location	location
bool	implicit = false
	Whether the language bound it rather than the author: the index every loop provides.
bool	readable = true
	Whether a pipeline may read it.
bool	writable = false
	Whether a pipe may write it.
std::string	action
	For a call: the action named, whether it was try, and the sibling flow it resolves to if it is one.
bool	tolerant = false
const FlowPlan *absl_nullable	target = nullptr
int	reads = 0
	How many times something read it, wrote it, or waited for it.
int	writes = 0
int	status_reads = 0
	For a call: whether anything read its status – wait x, status x, or a bound wait.
graph::RefId	ref = graph::kNone
	The graph ref this name reads and writes, when a graph was built: a port, a node, a header, a loop variable.
graph::StepId	step = graph::kNone
	The graph step this name is: a call, or a bound wait/drain.
graph::RefId	value_source = graph::kNone
	For a value a let bound: the stream it took a value of, and which value of that stream it is.
int	value_offset = 0
std::string	pattern
	The match pattern this value came out of, where it came out of a literal one.
bool	value_part = false
	Whether this name is one part of a value a let took apart.

Detailed Description

One name, what it is, and what became of it.

The usage counts are here rather than in the inspector because the resolver is the pass that walks every reference: counting as it goes costs nothing, and an inspector that walked the tree again to find out would be a second implementation of name resolution.

Member Data Documentation

action

std::string a11::flow::Symbol::action

For a call: the action named, whether it was try, and the sibling flow it resolves to if it is one.

implicit

bool a11::flow::Symbol::implicit = false

Whether the language bound it rather than the author: the index every loop provides.

Nothing is said about one of these going unread.

kind

SymbolKind a11::flow::Symbol::kind = SymbolKind::kInputPort

location

syntax::Location a11::flow::Symbol::location

name

std::string a11::flow::Symbol::name

pattern

std::string a11::flow::Symbol::pattern

The match pattern this value came out of, where it came out of a literal one.

A pattern names its fields, so this is how the tooling knows what a value has without the language gaining a type system: the fields are in the text that made it. Empty for everything else, including a pattern computed at run time – nothing is known about those and offering a guess would be worse than offering nothing.

readable

bool a11::flow::Symbol::readable = true

Whether a pipeline may read it.

reads

int a11::flow::Symbol::reads = 0

How many times something read it, wrote it, or waited for it.

ref

graph::RefId a11::flow::Symbol::ref = graph::kNone

The graph ref this name reads and writes, when a graph was built: a port, a node, a header, a loop variable.

Memoised here because identity is the whole point – two mentions of one node are one stream, and skip n accumulates on it.

status_reads

int a11::flow::Symbol::status_reads = 0

For a call: whether anything read its status – wait x, status x, or a bound wait.

A try whose status nobody reads is the flow ignoring the failure it just said it expected.

step

graph::StepId a11::flow::Symbol::step = graph::kNone

The graph step this name is: a call, or a bound wait/drain.

target

const FlowPlan* absl_nullable a11::flow::Symbol::target = nullptr

tolerant

bool a11::flow::Symbol::tolerant = false

value_offset

int a11::flow::Symbol::value_offset = 0

value_part

bool a11::flow::Symbol::value_part = false

Whether this name is one part of a value a let took apart.

A fact rather than something inferred from value_source being absent: the editor path builds no graph, so every ref is absent there and a check that read the ref would be a check an editor never runs.

value_source

graph::RefId a11::flow::Symbol::value_source = graph::kNone

For a value a let bound: the stream it took a value of, and which value of that stream it is.

advance reads both to bind the next one, which is what makes "the first use sees the first value" a fact rather than a hope.

writable

bool a11::flow::Symbol::writable = false

Whether a pipe may write it.

writes

int a11::flow::Symbol::writes = 0

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The documentation for this struct was generated from the following file:

• cpp/a11/flow/resolve.h