🧚 Wisp Language Specification (WIP-- pre-v1)

✨ Overview

Wisp is a declarative, whitespace-sensitive DSL for defining human-readable, structured schemas with expressive constraints.

Its primary goals are:

• Clarity — schemas are designed to be read and written by humans.
• Expressiveness — rich constraint logic, defaults, and validation hints.
• Tooling-agnostic — usable across runtimes (LLMs, JSON Schema, codegen, etc.)

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Syntax Rules

🧐 Show Me

@wisp:meta(
  version = "1.0.0"
  name = "My Schema"
)

User:
  name      string:min(1)
  email     string:email:min(5):max(50)
  ?age      int:min(0):max(27) :is(120) = 27 "uncool age bro"
  height    int:all(:min(100), :max(300))
  verified  boolean!:is(false) = true

---

🧑‍💻 Field Definitions

[?]fieldName  [type] [:constraint[:...]] [= default] ["validation message"]

Component	Description
? (optional)	Visual-only cue for optional fields. Optional fields are defined by = default, not this symbol.
fieldName	Required. Alphanumeric with _ and -.
type	Optional. Defaults to string.
:constraint	Optional. Colon-prefixed constraint expressions (can be nested or negated).
= default	Optional. If present, field is optional.
"message"	Optional. Always comes last if present. Overrides inferred validation message.

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🔗 Constraint Syntax

• Constraints start with : and can be chained for AND logic
• One or more spaces between constraints = OR logic
• Negation uses !: before the constraint

✅ Constraint Examples:

:min(0):max(10)                 # AND
:min(0)  :is(999)               # OR
!:is(false)                     # NOT
:all(:min(5), :max(10))           # ALL
:any(:is("yes"), :is("y"))      # ANY

---

🧬 Typing

✅ Primitives (and dates 😉)

• string
• int
• float
• boolean
• date

🚧 (Planned)

• array, object, map, set
• Constructor-style: String, Number, Date, etc.

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🎭 Constraint Aliasing

@age  :min(0):max(120)

User:
  ?age  int:age = 27 "cool age bro"

• Define reusable constraint aliases using @name :constraint...
• Only constraints may be aliased — not types or record names

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💬 Validation Messages

• Optional custom validation messages follow the default value:

?email  string:email = "no-reply@example.com" "Must be a valid email."

• If omitted, inferred messages are generated:

age must be at least 0; age must not exceed 120; age must equal 120

---

📚 Meta Block

@wisp:meta(
  version = "1.0.0"
  name = "My App Schema"
)

• Declares schema-level metadata like version and schema name

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🔜 Post-Parse Features

• Whitespace-sensitive logic resolution (AND vs OR)
• Emission of JSON Schema (and eventually YAML, TOML, TS, etc.)
• Support for :re(...) constraints with regex-based pattern inference