Module meta 

#[deftly(...)] meta attributes

Used meta checking

Most of this file is concerned with generating accurate and useful messages when a driver is decorated with #[deftly(...)] attributes which are not used by any template.

We distinguish “used” metas from “recognised” ones.

“Used” ones are those actually tested, and used, during the dynamic expansion of the template. They are recorded in the PreprocessedMetas, which contains a Cell for each supplied node.

“Recognised” ones are those which appear anywhere in the template. These are represented in a data structure [``Recognised]. This is calculated by scanning the template, using the FindRecogMetas` trait.

Both of these sets are threaded through the ACCUM data in successive template expansions; in the final call (EngineFinalInput), they are combined together, and the driver’s metas are checked against them.

Re-exports

pub use FoundNearbyNodeKind as FNNK;

pub use FoundNodeKind as FNK;

Macros

impL_find_recog_metas_via_deref 🔒

impL_find_recog_metas_via_iter 🔒

Structs

Accum

Information for meta checking, found in accumulation

BorrowedDesig 🔒

Desig

Meta designator eg fmeta(foo(bar))

DisplayAsIfSpecified 🔒

Displays as a #[deftly(...)] as the user might write it

FoundNearbyNode

Information about a nearby meta node we found

FoundNode

Node in tree structure found in driver #[deftly(some(thing))]

IsUsed

Label

(foo(bar)) in eg fmeta(foo(bar))

MetaUnsupported

newtype to avoid coherence - it doesn’t impl Parse + ToTokens

PreprocessedTree

An #[deftly()] attribute, or a sub-tree within one

PreprocessedValueList

A part like (foo,bar(baz),zonk="value")

Recognised

ScopeIter

An iterator over the variants of Scope

SubstAsSupported

SubstMeta

SuppliedScopeIter

An iterator over the variants of SuppliedScope

UsageInfo

UsageModeIter

An iterator over the variants of UsageMode

UsedChecker 🔒

UsedGroup

One lot of used metas in accumulation - argument to a _meta_used accum

Enums

CheckUsed

Something representing possibly checking that meta attributes are used

FoundNearbyNodeKind

How the nearby node relates to the one we were looking for

FoundNodeKind

Node in tree structure found in driver #[deftly(some(thing))]

PreprocessedValue

Content of a meta attribute

Scope

Indicates one of fmeta, vmeta or tmeta

SubstAs

SuppliedScope

Scope of a supplied meta (#[deftly(...)]) attribute

UsageMode

Traits

FindRecogMetas

SubstAsSupportStatus

Implemented for syn types supported in this build, and MetaUnsupported

Functions

metavalue_lit_as

Convert a literal found in a meta item into T

metavalue_litstr 🔒

Obtain the LiStr from a meta node value (ie, a Lit)

metavalue_spans 🔒

unrecognised_error 🔒

Type Aliases

PreprocessedMetas

#[deftly(...)] helper attributes

Usage

ValueExpr

ValueItems