Stdlib module json/types.vitl
This page is a wiki-style reference for one concrete stdlib file. It explains what the file owns, where it fits in the family, and how to decide whether this is the right surface to depend on.
json/types.vitl.Family: json
Kind: public stdlib surface
Page style: this reference follows the same “encyclopedic card + portrait + usage contract” logic as the keyword pages, but for stdlib modules.
Summary
- Overview
- Purpose
- Taxonomy
- Implementation profile
- Top-level API inventory
- Position in family
- Declaration map
- Representative signatures
- How to use this module
- User example
- Keyword coverage
- Source shape
- Source landmarks
- Source organization
- Complete API catalog
- Integration boundaries
- Composition guidance
- Relationship table
- Neighbor modules
Overview
| Field | Value |
|---|---|
| Path | json/types.vitl |
| Family | json |
| Kind | public stdlib surface |
| Line count | 54 |
| Declared procedures | 4 |
| Declared forms/picks | 4 |
`json/types.vitl` is a public stdlib surface inside the `json` family. It should be read as one focused slice of the broader family responsibility: Structured JSON surfaces including parse, parser, types, builder, schema, stringify, and serialize.
Purpose
This file should be chosen because of responsibility, not because its name “sounds close enough”. Inside the json family, it carries one focused part of the contract and keeps that responsibility separate from neighboring concerns.
- A build plan can be validated as domain data first and then exported to JSON in a separate step.
- A parser page should say how syntax becomes JSON values before serialization details appear.
Taxonomy
Think of this page as a generated encyclopedia entry rather than a hand-written tutorial. The goal is to show what kind of module this is, how dense it is, and what reading strategy makes sense before depending on it.
- Compact procedure surface: this file is small enough to read end-to-end before depending on it.
- Owns domain vocabulary: the module declares data shapes in addition to executable helpers, so its types are part of the contract.
- Minimal top-level dependencies: the module reads as mostly self-contained from its opening declarations.
- Explicit export surface: the file ends with visible export declarations instead of relying only on implicit namespace discovery.
Implementation profile
This profile is inferred directly from the source text. It does not replace reading the file, but it tells you quickly whether the module is mostly declarative, loop-heavy, branch-heavy, or organized around many small exits.
| Signal | Count | What it suggests |
|---|---|---|
if | 0 | Branching density and local decision-making. |
while | 0 | Loop-heavy or iterative implementation style. |
for | 0 | Collection-style traversal at source level. |
match | 0 | Variant-driven branching or grammar-style decoding. |
let | 1 | Local state and intermediate value density. |
give | 4 | Number of explicit exit points and result shaping. |
Top-level API inventory
| Surface | Items |
|---|---|
| Procedures | json_types_version, json_types_ready, json_types_manifest, json_types_selftest |
| Forms | JSONParser, JSONBuilder, JsonTypesManifest |
| Picks | JSONValue |
| Constants | none declared at top level |
| Exports | * |
Imported surfaces
This file does not advertise a top-level `use` surface in its opening declarations. That often means it is either self-contained or an aggregation layer.
Position in family
This file is module 8 of 8 in the json family when ordered by path. By procedure count it ranks 8, and by line count it ranks 6. Those ranks are useful as rough signals of breadth, not as quality judgments.
Declaration map
The declaration map turns raw source into a scan-friendly catalog. It is useful when the file is large enough that a reader wants to orient by kinds of surfaces first.
| Line | Name | Kind | Role |
|---|---|---|---|
| 1 | vitte/json/types | space | Declares the namespace that anchors this file in the stdlib tree. |
| 7 | JSONValue | pick | Introduces a tagged variant type used to model distinct outcomes. |
| 16 | JSONParser | form | Introduces a structured data shape that other procedures can exchange. |
| 22 | JSONBuilder | form | Introduces a structured data shape that other procedures can exchange. |
| 27 | JsonTypesManifest | form | Introduces a structured data shape that other procedures can exchange. |
| 33 | json_types_version | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 37 | json_types_ready | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 41 | json_types_manifest | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 49 | json_types_selftest | proc | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
The table is exhaustive for top-level declarations of the selected kinds. This file declares 9 matching surfaces.
Representative signatures
These signatures are shown in source order so the page keeps the feel of a reference manual, not just a keyword cloud.
pick JSONValue {(line 7)form JSONParser {(line 16)form JSONBuilder {(line 22)form JsonTypesManifest {(line 27)proc json_types_version() -> string {(line 33)proc json_types_ready() -> bool {(line 37)proc json_types_manifest() -> JsonTypesManifest {(line 41)proc json_types_selftest() -> bool {(line 49)
How to use this module
Start by reading the file as an ownership boundary. Ask three questions: what enters this module, what stable types or procedures it exports, and what adjacent module should stay outside of it.
- Read
spaceand top-level imports first so the ownership boundary ofjson/types.vitlis explicit. - Read declared forms and picks before algorithms so the data vocabulary is stable in your head.
- Traverse procedures in source order; the early helpers usually explain the naming and numeric conventions used later.
- Use the source landmarks section below as a table of contents when the file is large.
- Only after that compare neighbor modules, because the right boundary choice matters more than memorizing one helper name.
User example
This example is generated from the actual stdlib module surface. Its job is not to be the smallest snippet possible; its job is to show a realistic consumer-shaped file that exercises the module and mirrors the language keywords the module itself relies on.
space demo/json_types
form UserReport {
label: string,
ready: bool
}
pick UserOutcome {
case Ready(message: string)
case Empty(reason: string)
}
proc run_example() -> UserOutcome {
let result = json_types_version()
let ready: bool = json_types_ready()
let stable: bool = ready and true
give UserOutcome.Ready("ok")
}
export run_example
Keyword coverage
This table makes the “all keywords of the module” requirement auditable. It compares the detected Vitte keywords in the source file with the generated consumer example above.
| Keyword | Present in module source | Used in generated user example |
|---|---|---|
space | yes | yes |
form | yes | yes |
pick | yes | yes |
proc | yes | yes |
let | yes | yes |
give | yes | yes |
export | yes | yes |
true | yes | yes |
and | yes | yes |
The generated snippet exercises every detected Vitte keyword used by this module.
Source shape
space vitte/json/types
pick JSONValue {
JsonNull,
JsonBool(value: int),
JsonNumber(value: f64),
JsonString(value: string),
JsonArray(items: [JSONValue]),
JsonObject(keys: [string])
}
form JSONParser {
The excerpt is not meant to replace the file. It exists to make the module recognizable at first glance, the same way a Wikipedia infobox helps the reader orient before reading the whole article.
Source landmarks
Large files are easier to retain when they have visible landmarks. When the source contains explicit section banners, they are surfaced here; otherwise the first major declarations are used as anchors.
- JSON Types and Data Structures Module
Source organization
When a file carries its own internal chaptering, those chapters usually reveal the intended reading order better than a flat symbol list. This section reconstructs that organization from the source itself.
Opening declarations
Top-level items: 1. Procedures: 0. Data surfaces: 0. Constants: 0.
First visible names: vitte/json/types
JSON Types and Data Structures Module
Top-level items: 9. Procedures: 4. Data surfaces: 4. Constants: 0.
First visible names: JSONValue, JSONParser, JSONBuilder, JsonTypesManifest, json_types_version, json_types_ready, json_types_manifest, json_types_selftest, *
Complete API catalog
This catalog is the exhaustive file-level index for the module. It is intentionally closer to a generated encyclopedia appendix than to a tutorial summary.
Data surfaces
| Line | Name | Signature | Role |
|---|---|---|---|
| 7 | JSONValue | pick JSONValue { | Introduces a tagged variant type used to model distinct outcomes. |
| 16 | JSONParser | form JSONParser { | Introduces a structured data shape that other procedures can exchange. |
| 22 | JSONBuilder | form JSONBuilder { | Introduces a structured data shape that other procedures can exchange. |
| 27 | JsonTypesManifest | form JsonTypesManifest { | Introduces a structured data shape that other procedures can exchange. |
Procedures
| Line | Name | Signature | Role |
|---|---|---|---|
| 33 | json_types_version | proc json_types_version() -> string { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 37 | json_types_ready | proc json_types_ready() -> bool { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 41 | json_types_manifest | proc json_types_manifest() -> JsonTypesManifest { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
| 49 | json_types_selftest | proc json_types_selftest() -> bool { | Represents one top-level surface in the file contract and should be read as part of the module boundary. |
Exports
| Line | Name | Signature | Role |
|---|---|---|---|
| 54 | * | export * | Re-exports surfaces that the module wants to expose as part of its public boundary. |
Integration boundaries
Within json, this file should remain focused. If a future helper changes the host boundary, scheduling boundary, or data-shape boundary, it probably belongs in a neighbor module instead of being added here by convenience.
- Family responsibility: Structured JSON surfaces including parse, parser, types, builder, schema, stringify, and serialize.
- Family architecture role: Use `json` when data must cross a structured textual boundary. This family owns JSON shape and conversion, not business validation itself.
Composition guidance
Choose this module when
- Choose
json/types.vitlwhen the main question is owned by this module rather than by transport, storage, orchestration, or user-interface code. - A build plan can be validated as domain data first and then exported to JSON in a separate step.
- A parser page should say how syntax becomes JSON values before serialization details appear.
Pause before extending it when
- Avoid extending this file when the new helper mostly changes the boundary to host I/O, runtime coordination, or foreign integration instead of staying inside
json. - Check nearby modules such as
json/builder.vitl,json/parse.vitl,json/parser.vitlbefore adding convenience wrappers here.
Relationship table
This table keeps the page closer to a real encyclopedia entry: a module is easier to understand when compared with its nearest alternatives in the same family.
| Neighbor | Procedures | Data surfaces | Why compare it |
|---|---|---|---|
json/builder.vitl | 17 | 3 | Shares the same family boundary but carries a distinct slice of responsibility. |
json/parse.vitl | 11 | 3 | Shares the same family boundary but carries a distinct slice of responsibility. |
json/parser.vitl | 11 | 0 | Shares the same family boundary but carries a distinct slice of responsibility. |
json/schema.vitl | 9 | 2 | Shares the same family boundary but carries a distinct slice of responsibility. |
json/serialize.vitl | 10 | 1 | Shares the same family boundary but carries a distinct slice of responsibility. |
json/stringify.vitl | 10 | 2 | Shares the same family boundary but carries a distinct slice of responsibility. |
json.vitl | 41 | 11 | Shares the same family boundary but carries a distinct slice of responsibility. |