ts-expression-evaluator
Context-based expression evaluator.
install
- npm
npm install ts-expression-evaluator
- yarn
yarn add ts-expression-evaluator
Quick start
import evaluate, { registerFunction } from 'ts-expression-evaluator'
const context = {
id: 10,
name: 'FED',
count: 10,
staffs: [{
id: 1,
name: 'Tina'
}, {
id: 2,
name: 'James'
}],
}
evaluate('1+2')
evaluate('name', context)
evaluate('staffs[0].name', context)
evaluate('count + 10', context)
evaluate('count === 11', context)
registerFunction('IF', (condition, ifTrue, ifFalse) => {
return condition ? ifTrue : ifFalse;
})
evaluate('IF(name === 'FED', 'It\'s FED.', 'It\'s not FED.')') // It's FED.
evaluate('staffs[this.id === 1]', context)
Details
Unary Operators
Binary Operators
Operation | Symbol |
---|
Add, Concat | + |
Subtract | - |
Multiply | * |
Divide | / |
Logical Operators
Operation | Symbol |
---|
Logical AND | && |
Logical OR | || |
Comparisons
Comparison | Symbol |
---|
Equal | == |
Not equal | != |
Greater than | > |
Greater than or equal | >= |
Less than | < |
Less than or equal | <= |
Native Types
Type | Examples |
---|
Booleans | true , false |
Strings | "Hello "user"", 'Hey there!' |
Numerics | 6, -7.2, 5, -3.14159 |
Arrays | ['hello', 'world!'] |
API
evaluate(exp: string, context: object): any
registerFunction(name: string, func: Function): void
registerFunctions(funcs: {[key: string]: Function}): void
License
MIT