Powerful formula-syntax evaluator for Apex and LWC.

Features

• Supports all the most important operators and functions available in Salesforce formulas
• Support for lists and maps, including spread operator (...) support.
• Automatically understands relationships and can extract data from child records
• Comment support
• String interpolations
• Pre-built LWC component to evaluate Expressions in record pages and Experience Builder sites
• And much more!

Examples

Basic Math Operations

Object simpleMath = expression.Evaluator.run('(1 + 1) * 10');
System.debug(simpleMath); // 20

Object respectsPemdas = expression.Evaluator.run('1 + 1 * 10 + 50 * 20 / 100 + (20 * 20 /10)');
System.debug(respectsPemdas); // 61

String Operations

Object simpleConcat = expression.Evaluator.run('"👋 hello " + "there!"');
System.debug(simpleConcat); // 👋 hello there!

Id recordId = '001Oy00000GkWjfIAF';
Object interpolation = expression.Evaluator.run('"👋 hello ${Name}"', recordId);
System.debug(interpolation); // 👋 hello Acme Inc.

Advanced Operations

// Calculating if a year is a leap year
Id recordId = '001Oy00000GkWjfIAF';
Object result = expression.Evaluator.run('OR(\n' +
    '  MOD( YEAR( DATEVALUE(CreatedDate) ), 400 ) = 0, \n' +
    '  AND( \n' +
    '   MOD( YEAR( DATEVALUE(CreatedDate) ), 4 ) = 0,\n' +
    '    MOD( YEAR( DATEVALUE(CreatedDate) ), 100 ) != 0\n' +
    '  )\n' +
    ')', recordId);
System.debug(result); // true

// Determining the the region of an address
Id recordId = '001Oy00000GkWjfIAF';
Object result = expression.Evaluator.run('IF(ISBLANK(BillingState), "None",\n' +
    'IF(CONTAINS("AK:AZ:CA:HA:NV:NM:OR:UT:WA", BillingState), "West",\n' +
    'IF(CONTAINS("CO:ID:MT:KS:OK:TX:WY", BillingState), "Central",\n' +
    'IF(CONTAINS("CT:ME:MA:NH:NY:PA:RI:VT", BillingState), "East",\n' +
    'IF(CONTAINS("AL:AR:DC:DE:FL:GA:KY:LA:MD:MS:NC:NJ:SC:TN:VA:WV", BillingState), "South",\n' +
    'IF(CONTAINS("IL:IN:IA:MI:MN:MO:NE:ND:OH:SD:WI", BillingState), "North", "Other"))))))', recordId);
System.debug(result); // South

Using Lists and Maps

Object listExample = expression.Evaluator.run('[1, 2, 3]');
System.debug(listExample); // (1 2 3)

Object mapExample = expression.Evaluator.run('{"key": "value"}');
System.debug(mapExample); // {key=value}

Piping Complex Operations

Id recordId = '001Oy00000GkWjfIAF';
Object result = expression.Evaluator.run(
    'ChildAccounts ' +
        '-> WHERE(AnnualRevenue > 200) ' +
        '-> WHERE(NumberOfEmployees > 10) ' +
        '-> MAP(Name)',
    recordId);
System.debug(result); // (Acme Inc. Acme Subsidiary)

Declaring Custom Functions

String expr = 'fun factorial(n) => IF(n = 0 || n = 1, 1, n * factorial(n - 1));\n' +
    '\n' +
    'factorial(5)';
Object result = Evaluator.run(expr);
System.debug(result); // 120

Documentation

Table of Contents

• Introduction
  • Getting Started
  • Installation
  • Try
• Usage
  • Evaluating Expressions
  • Accessing Contextual Data
  • Configuring the evaluation
• Language Features
  • Lists
  • Maps
  • Piping
  • Declaring Functions
  • Anonymous Functions
  • String Interpolation
  • Querying Record Data
  • Referencing Org Data
  • Comments
• Standard Library
  • Operators
  • Functions
• Advanced Usage
  • Custom Functions
  • Apex Interoperability
  • Providing More Context To Your Expressions
• Components
  • Getting Started with Expression Components
  • Accordion
  • Alert
  • Avatar
  • Banner
  • Button
  • Avatars (Stacked)
  • Features
  • Form Builder
  • Formula
  • Hero
  • Input Text
  • Nav Bar
  • Logos
  • People
  • Pricing Table
  • Stats
  • Text Block

For the full Expression language documentation, please visit cesarparra.github.io/expression/.

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Contributing

Contributions are welcome! Feel free to open an issue or submit a pull request.

Setup

Create a scratch org by running:

sf org create scratch -f config/dev.json -a Expression --set-default

Push the source to the scratch org:

sf project deploy start

Assign the Expression Admin permission set to the default user:

sf org assign permset -n Expression_Admin

Debugging

While debugging, you might find it helpful to see the generated AST for a given expression.

The source code includes a Visitor implementation whose sole purpose is to do this, AstPrinter. When enabled, it will print the AST to the logs.

You can enable it by passing an expression.Configuration option to the run method with the printAst option enabled :

expression.Configuration config = new expression.Configuration().printAst();
Object value = expression.Evaluator.run('AND(true, false, 1=1)', config);
// Outputs to the logs:
// (AND true false (= 1 1))

Running tests

Run the tests with:

sf apex test run