Shorthand Syntax

The verbose DSL is readable but heavy for simple rules. Shorthand cuts the ceremony — symbolic operators, dotted property paths, and -> for the outcome — while producing the exact same Rule / RuleSet model. There are no evaluator changes; shorthand and verbose rules can live side by side in the same policy.

At A Glance

Verbose:

A **applicant** gets manual_review
if the __risk_score__ of the **applicant** is greater than 72.

Shorthand:

if applicant.risk_score > 72 -> manual_review.

Both produce the same outcome manual_review against the same data.

Interactive Example

Reset

Policy Rule

if applicant.risk_score > 72 -> manual_review.

if applicant.risk_score > 72 -> manual_review.

Test Data (JSON)

{
  "applicant": { "risk_score": 80 }
}

{ "applicant": { "risk_score": 80 } }

Run

Anatomy

[label:] if <condition> [and|or <condition> ...] -> <outcome>.

• label: (optional) — names the rule, same role as the verbose label. prefix.
• if introduces the condition.
• <condition> is a property comparison, list/string/unary check, or $label reference.
• and / or chain conditions.
• -> <outcome> declares the outcome and ends with a period.

Conditions

Comparison

Operator	Meaning
==	equal
!=	not equal
>	greater than
<	less than
>=	greater than or equal
<=	less than or equal

if user.role == "admin" -> access.

Interactive Example

Reset

Policy Rule

if user.role == "admin" -> access.

if user.role == "admin" -> access.

Test Data (JSON)

{
  "user": { "role": "admin" }
}

{ "user": { "role": "admin" } }

Run

And / Or

Interactive Example

Reset

Policy Rule

if applicant.risk_score > 72 and applicant.age < 25 -> manual_review.

if applicant.risk_score > 72 and applicant.age < 25 -> manual_review.

Test Data (JSON)

{
  "applicant": { "risk_score": 80, "age": 22 }
}

{ "applicant": { "risk_score": 80, "age": 22 } }

Run

Interactive Example

Reset

Policy Rule

if user.role == "admin" or user.level >= 5 -> access.

if user.role == "admin" or user.level >= 5 -> access.

Test Data (JSON)

{
  "user": { "role": "guest", "level": 7 }
}

{ "user": { "role": "guest", "level": 7 } }

Run

Lists — in / not in

Membership against a literal list of values.

Interactive Example

Reset

Policy Rule

if user.role in ["admin", "moderator"] -> access.

if user.role in ["admin", "moderator"] -> access.

Test Data (JSON)

{
  "user": { "role": "moderator" }
}

{ "user": { "role": "moderator" } }

Run

Interactive Example

Reset

Policy Rule

if user.role not in ["banned"] -> allowed.

if user.role not in ["banned"] -> allowed.

Test Data (JSON)

{
  "user": { "role": "guest" }
}

{ "user": { "role": "guest" } }

Run

Nested properties

Property paths are dot-delimited and can drill arbitrarily deep.

Interactive Example

Reset

Policy Rule

if user.address.country == "US" -> domestic.

if user.address.country == "US" -> domestic.

Test Data (JSON)

{
  "user": { "address": { "country": "US" } }
}

{ "user": { "address": { "country": "US" } } }

Run

exists

Property is present and non-null.

Interactive Example

Reset

Policy Rule

if user.email exists -> contactable.

if user.email exists -> contactable.

Test Data (JSON)

{
  "user": { "email": "a@b.com" }
}

{ "user": { "email": "a@b.com" } }

Run

is null

Property is null or missing — both forms satisfy is null.

Interactive Example

Reset

Policy Rule

if user.phone is null -> missing_phone.

if user.phone is null -> missing_phone.

Test Data (JSON)

{
  "user": { "phone": null }
}

{ "user": { "phone": null } }

Run

between

Numeric range, inclusive on both ends.

Interactive Example

Reset

Policy Rule

if user.age between 18 and 65 -> eligible.

if user.age between 18 and 65 -> eligible.

Test Data (JSON)

{
  "user": { "age": 18 }
}

{ "user": { "age": 18 } }

Run

contains

On a list, checks membership:

Interactive Example

Reset

Policy Rule

if user.tags contains "admin" -> flagged.

if user.tags contains "admin" -> flagged.

Test Data (JSON)

{
  "user": { "tags": ["admin", "verified"] }
}

{ "user": { "tags": ["admin", "verified"] } }

Run

On a string, contains requires full equality — it is not a substring match. For substring matching, use a verbose rule with the appropriate string operator.

Labels and References

Prefix a shorthand rule with label: to name it:

risk_check: if applicant.risk_score > 72 -> manual_review.

Dot-notation labels work just like in the verbose syntax:

risk.check: if applicant.risk_score > 72 -> manual_review.

Reference a labeled rule with $label (or not $label to invert):

Interactive Example

Reset

Policy Rule

risk_check: if applicant.risk_score > 72 -> manual_review.
if $risk_check and user.verified == true -> approved.

risk_check: if applicant.risk_score > 72 -> manual_review. if $risk_check and user.verified == true -> approved.

Test Data (JSON)

{
  "applicant": { "risk_score": 80 },
  "user": { "verified": true }
}

{ "applicant": { "risk_score": 80 }, "user": { "verified": true } }

Run

Interactive Example

Reset

Policy Rule

risk_check: if applicant.risk_score > 72 -> manual_review.
if not $risk_check -> denied.

risk_check: if applicant.risk_score > 72 -> manual_review. if not $risk_check -> denied.

Test Data (JSON)

{
  "applicant": { "risk_score": 50 }
}

{ "applicant": { "risk_score": 50 } }

Run

Multi-line Rules

A shorthand rule can span multiple lines for readability:

Interactive Example

Reset

Policy Rule

if applicant.risk_score > 72
 and applicant.age < 25
 -> manual_review.

if applicant.risk_score > 72 and applicant.age < 25 -> manual_review.

Test Data (JSON)

{
  "applicant": { "risk_score": 80, "age": 22 }
}

{ "applicant": { "risk_score": 80, "age": 22 } }

Run

Mixing Shorthand and Verbose

Shorthand and verbose rules coexist in the same rule set, and either can reference the other.

The Golden Rule constraint

Every policy needs exactly one golden rule — the top-level rule that nothing else references. Every other rule must be reachable from it via a label or selector reference. This applies whether the rules are shorthand, verbose, or a mix.

The example below fails to parse because both rules are top-level — neither references the other:

if applicant.risk_score > 72 -> manual_review.

A **applicant** gets approved
if the __income__ of the **applicant** is greater than 50000.

Parse error: Multiple global rules found: 'manual_review', 'approved'.
There should be only one golden rule that is not referenced by other rules.

A working mix

Label the supporting rule and reference it from the golden rule:

Interactive Example

Reset

Policy Rule

risk: if applicant.risk_score > 72 -> manual_review.

A **applicant** gets approved
if the __income__ of the **applicant** is greater than 50000
and §risk passes.

risk: if applicant.risk_score > 72 -> manual_review. A **applicant** gets approved if the __income__ of the **applicant** is greater than 50000 and §risk passes.

Test Data (JSON)

{
  "applicant": { "risk_score": 80, "income": 60000 }
}

{ "applicant": { "risk_score": 80, "income": 60000 } }

Run

Here approved is the golden rule, and risk (shorthand, labeled) is reachable through the verbose §risk passes reference. The reverse also works — a shorthand golden rule can reference a verbose rule via $label.

Limitations

Shorthand favours the common case. The following are verbose-only:

• Arithmetic on the LHS — if user.age + 1 > 18 -> ok. does not parse. Use the verbose math expression syntax instead.
• Math functions (floor of, ceil of, round of, abs of) — verbose-only.
• @label value references — verbose-only.
• Quantifiers and selectors over collections — use the verbose every / any forms.

If you need any of these in a rule, write that rule in verbose form. You can still mix it with shorthand rules in the same policy.

Operator Cheat Sheet

Shorthand	Verbose equivalent
x == y	is equal to
x != y	is not equal to
x > y	is greater than
x < y	is less than
x >= y	is greater than or equal to
x <= y	is less than or equal to
x in [...]	is in
x not in [...]	is not in
x between a and b	is between
x contains y	contains
x exists	exists
x is null	is null
$label	§label passes
not $label	§label fails
->	rule outcome (gets, is, etc.)