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Table of Contents

Everything within the C3 AI Suite is managed through or exists as a C3 .ai Type. C3. ai Types allow users to describe, process, and interact with data and analytics. Broadly speaking, C3 .ai Types are like Java classes, and include 'fields', 'methods', and an inheritance structure. Once you understand the structure of C3 .ai Type, Types you will be able to write C3.ai Types to load data, run analytics, build and deploy machine learning models, and configure application logic , for your research project. 

All C3 .ai Types are defined in a .c3typ file, stored in 'src' directory of a C3.ai Package. (We'll get to C3.ai Packages a little later)package. A .c3typ file can only define a single C3 .ai Type. The .c3type c3typ file name must match the name of the C3 .ai Type being defined. 

First, In this section we will describe the C3.ai Package, package to download for this tutorial . Then, then we will discuss the syntax, special keywords, fields, methods, and inheritance structure of C3 .ai Types. Finally, we will review some examples.

lightbulbAD

...

Package

In this tutorial , we will use the lightbulbAD C3.ai package. To download the source code for this package, please follow the instructions available here: Guide to download C3 lightbulbAD Package.

Syntax

 To help familiarize yourself with the syntax for a C3 .ai Type, let's look at how the 'SmartBulb' Type is defined in the lightbulbAD C3.ai Package:package:

/*
 * Copyright 2009-2020 C3 (www.c3.ai). All Rights Reserved.
 * This material, including without limitation any software, is the confidential trade secret and proprietary
 * information of C3 and its licensors. Reproduction, use and/or distribution of this material in any form is
 * strictly prohibited except as set forth in a written license agreement with C3 and/or its authorized distributors.
 * This material may be covered by one or more patents or pending patent applications.
 */

/**
 * A single light bulb capable of measuring various properties, including power consumption, light output, etc.
 */
entity type SmartBulb extends LightBulb mixes MetricEvaluatable, NLEvaluatable type key "SMRT_BLB" {

  /**
   * This bulb's historical measurements.
   */
  bulbMeasurements: [SmartBulbMeasurementSeries](smartBulb)

   /**
    * This bulb's historical predictions.
    */
   @db(order='descending(timestamp)')
   bulbPredictions: [SmartBulbPrediction](smartBulb)

   /**
    * This bulb's latest prediction.
    */
   currentPrediction: SmartBulbPrediction stored calc "bulbPredictions[0]"

   /**
    * This bulb's historical events.
    */
   bulbEvents: [SmartBulbEvent](smartBulb)

   /**
    * The latitude of this bulb.
    */
   latitude: double

   /**
    * The longitude of this bulb.
    */
   longitude: double

   /**
    * The unit of measurement used for this bulb's light output measurements.
    */
   lumensUOM: Unit

   /**
    * The unit of measurement used for this bulb's power consumption measurements.
    */
   powerUOM: Unit

   /**
    * The unit of measurement used for this bulb's temperature measurements.
    */
   temperatureUOM: Unit

   /**
    * The unit of measurement used for this bulb's voltage measurements.
    */
   voltageUOM: Unit

   /**
    * A SmartBulb is associated to a {@link Fixture} through a SmartBulbToFixtureRelation.
    */
   @db(order='descending(start), descending(end)')
   fixtureHistory: [SmartBulbToFixtureRelation](from)

   /**
    * The current Fixture to which this bulb is attached.
    */
   currentFixture: Fixture stored calc 'fixtureHistory[0].(end == null).to'

   /**
    * Method to determine the expected lumens of a light bulb
    */
   expectedLumens: function(wattage: !decimal, bulbType: !string): double js server

   /**
    * Returns the life span of this smartBulb
    */
   lifeSpanInYears: function(bulbId: string): double js server

   /**
    * Returns the average life span of all smartBulbs.
    */
   averageLifeSpan: function(): double js server

   /**
    * Returns the id of the smart bulb with the shortest recorded life span to date.
    */
   shortestLifeSpanBulb: function(): string js server

   /**
    * Returns the id of the smart bulb with the longest recorded life span to date.
    */
   longestLifeSpanBulb: function(): string js server

}

At a glance, a .c3typ file has the following components: 

  • Keywords, which define the name, inheritance structure, and properties of a C3 Type.ai Type
  • Fields, which define attributes or data elements on a C3 Type.ai Type
  • Methods, which define business logic on C3 Types.ai Types
  • Annotations like '@db', which often precede fields or methods , and further configure the behavior of a C3 Type.ai type
  • Constants such as strings or integers.
  • Comments which aren't parsed by C3 , and instead provide a message to the developer.

At a high level, the basic syntax to define C3 .ai Type Types is as follows (originally from official C3.ai Type documentation here: https://developer.c3.ai/docs/7.12.17/topic/mda-types

...

[remix,

...

extendable]

...

[entity]

...

type

...

TypeName

...

extends,

...

mixes

...

AnotherType

...

{

...


    /*

...

comments

...

*/

...


    [field

...

declaration]

...


    [method

...

declaration]

...


}

Note: Everything within square brackets '[]' is optional.C3.ai Resources on C3.ai Types:

Additional Resources

Keywords

A C3 .ai Type definition is introduced with a series of keywords. These keywords tell the C3 AI Suite how to construct this typeType, store it internally, and whether it inherits fields and methods from other already defined C3 .ai Types. We describe each:

  • type: All .c3typ files have the keyword 'type'. This keyword tells the C3 AI Suite that this file defines a C3 .ai Type. 
  • entity: The keyword 'entity' keyword indicates the C3 .ai Type is a 'Persistable' (i.e., needs to be stored in a database in the C3 AI Suite). Since a large majority of C3 .ai Types are Persistable, 'entity' is an important keyword to include in .c3typ files. 
  • mixes: Adding the keyword `mixes AnotherType``mixes <AnotherType>`, a C3 .ai Type Type inherits the properties (e.g., fields, methods) of `AnotherType`<AnotherType>'. A C3 .ai Type can mix-in multiple Types. 
  • remixes: Adding the keyword`remix AType`, allows C3.ai keyword`remix <AType>` allows a developer to modify an existing C3 .ai Type (e.g., add new fields or methods, update existing fields or methods). Re-mixing is useful when you don't have access to the original .c3type c3typ file for a particular C3 .ai Type, but wish to edit that C3 .ai Type. 
  • extends: C3.ai developers Developers often add the keyword `extends AnotherType`, `extends <AnotherType>` to define a subclass of a particular C3 .ai Type (e.g., SmartBulb extends Lightbulb). The extension Type (i.e., Smartbulb) inherits all the fields and methods of the original Type (i.e., Lightbulb). Additionally, data associated with the extension and original C3 .ai Types are stored in the same database table. Therefore, you must specify a `type key`(on `type key`on the extension Type ), so the C3 AI Suite can distinguish data associated with the extension and original C3 .ai Types. Please note , a C3 .ai Type can only extend ONE other Type. 
  • extendable: All extended Types (i.e., Lightbulb) MUST be marked with the keyword "extendable".  Under the covers, the keyword "extendable" tells the C3 AI Suite to add a field (called 'key') to the database table , storing the extended (or base) C3 .ai Type. This 'key' field is used to distinguish data associated with different varieties of the extended C3 .ai Type.
  • type key: All extension types Types (i.e., Smartbulb) MUST BE marked with the keyword 'type key VALUE<VALUE>' (e.g., "type key SMRT_BLB").
  • schema name: A set of keywords indicating the name of the database table , used to store data for a Persistable C3 .ai Type. Developer Developers specify a schema name to customize database table names.

To learn more about C3.ai Type Definitions, please see the C3.ai resources here:

Additional Resources

C3

...

Types 

There are many categories of C3 .ai Types. 

We will cover the most commonly used categories in this tutorial:

  • Primitive Types 
  • Persistable Types 
  • Generic (Parametric) Types 
  • Abstract Types 

Primitive Types

Like many programming languages, the C3 AI Suite has primitives. Primitives define the units (or data types) of fields on a C3 .ai Type (e.g., "int", "double", "float"). The C3 AI Suite includes a number of primitiveprimitives, listed below for reference. Adding new primitives will require support from the C3 .ai AI engineering team. However, however, most DTI researchers should be able to progress their research projects with the C3 AI Suite's existing primitives. C3 AI Suite Primitives

  • binary
  • boolean
  • byte
  • char
  • datetime
  • decimal
  • double
  • float
  • int
  • json
  • long int
  • string

To learn more about primitives, see the C3.ai Resources here:

Persistable Types

The most common C3.ai Type you will define is a 'Persistable' type. Persistable types store data in a C3 AI Suite database. By default, all Persistable types are stored in Postgres. However, Persistable types can also be stored in file systems (e.g., Azure Blob) or key-value stores (e.g., Cassandra), by adding an annotation to your .c3typ file (as will be discussed below). 

When defining a Persistable type, you MUST add the following two key terms to your .c3typ file

  1. entity: The keyword 'entity' keyword tells the C3 AI Suite this is a 'Persistable' type
  2. schema name: The schema names is the name of the database table, where the C3.a Type's data are stored. When defining a new Persistable type, you need to add the keywords 'schema name' followed by your chosen table name, in your .c3type file. (e.g., in the C3.ai Type LightBulb, we have 'schema name "LGHT_BLB"', where "LGHT_BLB" is our chosen table name). Please note, extended C3.ai DO NOT NEED a scheme name.

To learn more about 'Persistable' Types, please see the C3.ai Resources below: 

C3 Also supports certain composites of primitive types. For example, the C3 Type Mapp  is a map between values and keys. We can create a map directly in python in two ways:

  1. Let C3 Figure out the type for us: c3.MappObj(value=python_obj) The new Mapp object can be accessed through the .value  property of the MappObj
  2. Tell C3 exactly which types are supported with c3.Mapp(c3.MappType.fromString("map<string,any>"), {'a': 5, 'b': [1,2,3]})

Similarly, C3 has the Arry  type which supports plain arrays. We can specify them in the same ways.

  1. Let C3 Figure out the type for us: c3.ArryObj(value=python_list)  The new Arry  object can be accessed through the .value  property of the ArryObj
  2. Tell C3 exactly which types are supported with c3.Arry(c3.ArryType.fromString('[int]'), [1,2,3,4]) 

In both cases, these primitive types aren't persisted. They can be used anywhere a C3 Type specifies it must have an Obj  type. (Especially useful for DynBatchJobs  or DynMapReduce jobs for contexts).

Additional Resources

Persistable Types

The most common C3 Type you will define is a 'Persistable' Type. Persistable Types store data in a C3 AI Suite database. By default, all Persistable Types are stored in Postgres though they can also be stored in file systems (e.g., Azure Blob) or key-value stores (e.g., Cassandra), by adding an annotation to your .c3typ file (discussed below). 

When defining a Persistable type, you MUST add the following two key terms to your .c3typ file:

  1. entity: The keyword 'entity' keyword tells the C3 AI Suite this is a 'Persistable' Type.
  2. schema name: The schema names is the name of the database table where the C3 Type's data are stored. When defining a new Persistable Type, you need to add the keywords 'schema name' followed by your chosen table name, in your .c3typ file. (e.g., in the C3 Type LightBulb, we have 'schema name "LGHT_BLB"').
    Note: Extended C3 Types DO NOT NEED a scheme name and Schema names CANNOT exceed 30 characters. 

Additional Resources

Generic (Parametric) Types

Like a Java or C++ Class, C3 .ai Types can be parameterized (or genericized). In fact, the C3 AI Suite uses the exact same syntax as Java and C++ to define a typeType's parameters (i.e., angle brackets '<>' ). When defining a Generic (Parametric) typeType, your Type name will be followed by angle brackets and a comma-separated list of parameters (usually other C3 .ai Types).  For example:

Code Block
type TheType<V,U> {
	fieldA: V
	fieldB: [U]
}

Then, when using your Parametric Type in other places, you must specify the arguments for each parameter in the angle brackets. As example, you may define a new C3 .ai Type with the following field:

Code Block
type NewType {
	newField: TheType<TypeA, TypeB>
}

If your C3 .ai types Types will be heavily re-used by other C3.ai developers , you should consider using Parametric (Generic) typesTypes.

To learn more about Generic Types, please see the C3.ai Resources here:

Additional Resources

Fields

As discussed above, a C3 Type mainly consists of two components: fields and methods.

Fields are attributes or properties Each field of a C3 Type is defined by first giving the field name . To define a field on C3 Type, use the following syntax: field name, followed by a colon ':', followed by a Type.

The name must follow a set of conventions: – Name conventions here –

Depending on the Type of the field, the field is grouped into some broad categories.

Primitive Fields

Primitive Fields use types which are PrimitiveTypes. These are simple data types usually directly supported by database technologies such as SQL. These fields are stored directly within the main type's table.

Reference Fields

Reference Fields use another defined C3 Type. This reference is implemented in the main Type's table as a foreign key into the referenced Type's table, (The 'id' field!).

Collection Fields

Collection Fields are groups of Types. There are four broad categories of collections which can be used.

  • array: denoted by `[MyType]`
  • map: denoted by `map<int, MyType>` (the left argument is the key which can be any primitive type, while the right can be any Type.)
  • set: denoted by `set<MyType>`
  • stream: denoted by `stream<MyType>`. (This is a read-once type of collection).

When we define a field which is a collection of MyType, we can also specify which MyTypes get added by using Foreign Key Collection Notation. If for example, we're trying to define the new type TheType, and we want a collection to have type [MyType], but we don't want all MyTypes to be in this collection, we can use the notation `(thetype, id)` which specifies that C3 Should only use MyTypes whose 'thetype' property matches TheType's id property. Please see the section 'Foreign Key Collection Notation and Schema Names' in the following C3.ai documentation where this concept is explained better: https://developer.c3.ai/docs/7.12.17/topic/mda-fields

Calculated Fields

These fields are derived from other fields. Calculated fields are specified as follows

Code Block
fieldName: FieldType [stored] calc "field_formula"

So, like the other types, we first specify a type for the field, then we must use the keyword 'calc' followed by an expression formula. (e.g, in the SmartBulb example above, this is 'fixtureHistory[0].(end == null).to').

You may also specify the keyword 'stored'. With the stored keyword, the value of the field is stored in the Type's Table, while without it is calculated at runtime.

C3.ai Developer Resources on Fields:

...

ValueType (e.g., "lumens: int"). By convention, field names are camelCase.

A C3 Type can have many different kinds of fields. Here are the four most commonly used fields:

  • Primitive Fields 
  • Reference Fields 
  • Collection Fields 
  • Calculated Fields 

Primitive Fields

Like many other programming languages the C3 AI Suite has primitive fields (e.g., int, boolean, byte, double, datetime, string, longstring). For example:

doubleField: double
intField: int

Primitive fields are stored in a particular C3 Type's database table.

Reference Fields

Reference fields point (or refer) to other C3 Types. Reference fields link (or join) two C3 Types together. Under the covers, the Reference field stores a pointer (i.e., foreign key reference or ID) to record of another C3 Type. To define a Reference field, use the following syntax: field name, followed by colon ':', followed by Type Name (e.g., "building: Building"). For example:

refField: AnotherType

Collection Fields

Collection fields contain a list of values or records. There are four categories of collections fields:

  • array: denoted by `[MyType]` (contains an array of references to 'MyType').
  • map: denoted by `map<int, MyType>` (left argument is the key which can be any primitive type, right argument can be any C3 Type).
  • set: denoted by `set<MyType>`.
  • stream: denoted by `stream<MyType>`. (This is a read-once type of collection).

Collection fields can also be used to model one-to-many and many-to-many relationships between two C3 Types. To do so, we use the Foreign Key Collection Notation, which specifies the foreign key by which two C3 Types (i.e., ThisType and AnotherType) are joined.

To define this annotation use the following syntax: "fieldName :   `[AnotherType]` (fkey, key)" where:

  • 'fkey' is a field on `AnotherType' to use as the foreign key
  • 'key' is an optional field on ThisType, whose records should match those of the 'fkey' field on 'AnotherType' (defaults to `id` field of ThisType, if not specified).
  • In other words, the Collection field will contain pointers to all records in AnotherType, where ThisType.key == AnotherType.fkey.

For example:

fieldName: [AnotherType] (fkey[, key])

Shown in the example code and diagram below, the field bulbMeasurements, contains a list of all the SmartBulbMeasurementSeries records, where SmartBulb.id == SmartBulbMeasurements.smartBulb (e.g., a list of various measurements relevant to a SmartBulb, like temperature or power). 

Image Added

...

Please see the 'Foreign Key Collection and Schema Names" section in the following C3 AI Develop Documentation for more details: 

https://developer.c3.ai/docs/7.12.

...

25/

...

topic/

...

mda-fields

Calculated Fields

Calculated fields are derived from other fields on a C3 Type. Calculated fields typically included either JavaScript code or C3 AI ExpressionEngineFunctions and are specified as follows:

fieldName: FieldType [stored] calc "field_formula"

There are two types of calculated fields:

  1. Simple calculated fields: The values of these fields are calculated at runtime and not stored. To define a simple calculated field use the following syntax: keyword `calc`, followed by an expression formula.
  2. Stored calculated fields: The values of these fields are stored in the C3 Type's database table. To define a stored calculated field use the following syntax: keywords `stored calc`, followed by an expression formula (e.g, in the SmartBulb example above, 'stored calc fixtureHistory[0].(end == null).to').

Additional Resources

Methods

At a high-level, methods are pieces of code that take in arguments or parameters and return new values. To define a method on a C3 Type, use the following syntax, method name followed by a colon ':' followed by a function signature, (e.g., function() or function(wattage: !decimal, bulbType: !string)), followed by a colon ':', followed by a return parameter, along with an implementation language and execution location. 

Function Signatures

Here's the syntax for a method's function signature:

Code Block
function(parName1: [!] parType1, parName2: [!] parType2):

We see the keyword 'function' followed by a comma-separated list of input parameters. To define an input parameter, use the following syntax: argument

Methods

Each method of a C3 Type is defined by first giving the method name followed by a colon ':' followed by a function signature, (e.g., function() or function(wattage: !decimal, bulbType: !string)), followed by a colon ':', followed by a return Type, along with a language and environment specification.

Function Signatures

Instead of a Type name following the name as with fields, methods have a function signature. the syntax looks like:

Code Block
function(parName1: [!] parType1, parName2: [!] parType2):

we see 'function' followed by a comma separated list of argument definitions. An argument definition consists of a parameter name followed by a colon ':', followed by a Type name. Optionally, you can also include an '!' before the parameter type to indicate that that argument is required.

Return Types

After the function signature we have a return type. This must be a C3 type. The function must return an object of the appropriate type in the .

Language/Environment Specification

Finally, we end with a language and environment specification.

Language Specifications

  • py: Use the 'py' keyword to indicate this is a Python function.
  • js: Use the 'js' keyword to indicate this is a JavaScript function.

Currently, these are the only two languages which the C3 AI Suite supports for native method definitions

Environment Specification

Then, this is followed by an environment specification. for JavaScript the only two environments are:

  • server: This JavaScript function is executed within the C3 AI Suite by a worker node.
  • client: This JavaScript function is executed at the client browser.

, followed by argument type (e.g., bulbID: string). Optionally, you can also add an exclamation point '!' before the argument type to indicate the argument is required.

The function itself is NOT implemented in the .c3typ file, rather in a separate .js (JavaScript), .py (Python) or .r (R) files stored in the same directory as the .c3typ file. 

Return Parameter

Following the function signature is a return parameter. Return parameters must be a C3 Type. 

Implementation Language/Execution Location

Finally, let's discuss the implementation language and execution location.

Language Specifications

Methods can be implemented in JavaScript, Python, or R:

  • py: Use the 'py' keyword to indicate this is a Python method.
  • js: Use the 'js' keyword to indicate this is a JavaScript method.
  • r: Use the 'r' keyword to indicate this is an R method.

Currently, these are the only three programming languages natively supported by the C3 AI Suite to define methods. 

Execution Location

Methods can be executed in three locations:        

  • server: Indicates the method will run on the C3 AI Suite by a worker node. Server should be used for methods requiring high processing power (e.g., methods that fetch or create large amounts of data).
  • client: Indicates the method will run on the client's browser.
  • all: Indicates the method will run wherever it is called from. If the call comes from the browser, the function will execute in the browser. If the call comes from a server, the execution will happen in the server.

Please note, R and Python methods can only be executed on the server. Javascript methods can be executed in either the server or client.

Additionally, for For Python, we need to specify a valid 'ActionRuntime' for the python function to be executed in. ( ActionRuntimes are defined within the in C3 AI Suite , and new ones ActionRuntimes can be defined as part of a C3 Package. They in a package and are essentially conda environments. ) For example, 'server' will use the 'py-server' ActionRuntime.

Function Definitions

FinallyAs mentioned above, the function definition goes itself is defined in a different file from the Type definition .c3typ file. It should have The name of this file should be the same base name as the .c3typ definition file, but have an extension appropriate for the language of implementation file where the method is defined (e.g., SmartBulb.js and SmartBulb.c3typ), but have a different extension, per the function's implementation language (e.g., 'py' for Python, 'js' for JavaScript, 'r' for R). Within, the file must contain functions whose name matches the method name from the Type definition exactlyThe function names in this file must exactly match the method names in the .c3typ file. For example, if we have define a C3 Type defined like soas such: 

Code Block
entity type NewType {
	field: double
	funcA: function(num: !int) : float js server
    funcB: function(num: !int, name: string) : double py server
}

This type C3 Type will be defined in a file named called 'NewType.c3typ',  There will also have to be . We also need two other files, 'NewType.js' and 'NewType.py', in the same directory as 'NewType.c3typ'. Here's a peek inside:

'NewType.js'

...

Code Block
function funcB(num, name='default') {
    ...
}

...

Additional Resources

Inheritance

Like many modern languages, Types can also a Java or C++ Class, a C3 Type can inherit fields and methods from other types in an object oriented fashionC3 Types. The keywords which signal inheritance are `keywords`mixes` and `and `extends` signal inheritance. These keywords follow the name of the new type.new C3 Type's name in your .c3typ file.

These Where C3 Type inheritance differs from other languages, is that these two keywords signal two different types kinds of Type inheritance.

Mix-ins

This most basic Mix-ins are the most common type of inheritance is and signaled by the 'mixes' keyword. When a type C3 Type 'mixes' another typeC3 Type, it inherits all of the fields and methods of that type. The new type gets its own schema and table, and the user can go on to use it as they normally would.the original C3 Type. In general, mix-ins are used to incorporate non-persistable Types. The new C3 Type is stored in a new table and has its own schema. 

Code Block
type ParentType {
    fieldA: int
    funcA: function(): ReturnType
}

type ChildType mixes ParentType {
    fieldB: double
    funcB: function(): ReturnType
}

In this example, ChildType also includes the field and method defined in the parent typemixes ParentType, and inherits 'fieldA' and 'funcA' defined on ParentType.

Persistable Inheritance

This second type of Persistable inheritance is signaled by the 'extends' keyword. When a type C3 Type 'extends' another typeC3 Type, it inherits its all the original C3 Type's fields and methods, but also resides in the same schema and table as the original type. In fact, a type can only extend a type which has been marked as `extendable`.. The extension and original C3 Types must be marked with 'entity' keyword and share the same database table. To distinguish data from the original and extension C3 Types, the C3 AI Suite adds a 'type key' field to this database table. Additionally, only C3 Types marked with the `extendable` keyword can be extended. 

Code Block
extendable entity type ParentType schema name "PRT_TYP" {
    fieldA: int
    funcA: function(): ReturnType
}

entity type ChildType extends ParentType type key "CHLD" {
    fieldB: double
    funcB: function(): ReturnType
}

In this example, ParentType is an extendable Persistable type stored in schema the table 'PRT_TYP'. ChildType extends ParentType and uses is also stored in the table 'PRT_TYP'.  Records associated with ChildType have 'type key' == 'CHLD' to distinguish them from ParentType's data.C3.ai developer resources on Inheritance:

Additional Resources

Annotations

With annotations you can further configure a C3 Type. Annotations can appear before Type definitions, field declarations, and method declarations. They do a variety of things such as configure As example, annotations can be used to specify the database technology used to store that Type, mark what type of ActionRuntime should be used a C3 Type (e.g., Cassandra, Azure Blob), mark the ActionRuntime in which to run a particular method, Mark deprecate a field or method as deprecated or beta, Specify a timeseries treatment, and specify parameters of C3 Analytics (discussion to come soon). These are only a selection of what annotations can do., specify how time-series data should be treated, and specify how to trigger analytics or DFEs (DataFlow Events).

Here are a few examples of defining annotations: Here, we show a couple of examples:

Code Block
  /**
   * This bulb's historical predictions.
   */
  @db(order='descending(timestamp)')
  bulbPredictions: [SmartBulbPrediction](smartBulb)

The bulbPredictions field is annotated that the database should store the bulbPredictions With the `@db(order = 'descending(timestamp)'` annotation, the bulbPrediction field's records are stored in descending order by timestamp.

Code Block
@ts(treatment='avg')
lumens: double

The With the `@ts(treatment = 'avg') annotation, the value of the lumens field of a type be default is now going to use the 'AVG' treatment.C3.ai developer resources on Annotations:for a given SmartBulb is the average of all that Smartbulb's lumens data. 

Additional Resources

Final

...

Types

Types, methods, and fields can be made 'final' using the 'final' keyword. This prevents The fields and methods from being overridden by any type which mixes them in. If a type is made final, all fields and methods of that type are made finalof a Final Type cannot be modified or overridden (via 'mixes' or 'exends').

Code Block
type FinalType {
    final method: function(): string
}

...

Additional Resources

Abstract Types

The C3 AI Suite also supports abstract types. If you use To define an Abstract Type, add the keyword 'abstract' before the type definition, this will indicate an abstract type. You cannot instantiate an abstract type, and must mix it into another concrete typeType definition. Abstract Types cannot be instantiated and must mix-in to another concrete Type. This provides a great way to standardize interfaces. Here's an example:

Code Block
abstract type InteraceInterface {
	field1: int
    method1: function(double): int
}

...

Additional Resources

Examples

Look through the lightbulbAD package and find To see more examples of C3 Types, check out the .c3typ files . Look at these to see the range of possibilitiesin the lightbulbAD package: Guide to download C3 lightbulbAD Package.