Source: https://tanstack.com/db/latest/docs/reference/functions/walkExpression

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On this page

• Function: walkExpression()

• Parameters

• expr

• visitor

• Returns

• Example

walkExpression

Copy Markdown

Function: walkExpression()
==========================

ts

function walkExpression(expr, visitor): void;


function walkExpression(expr, visitor): void;

Defined in: packages/db/src/query/expression-helpers.ts:150

Generic expression tree walker that visits each node in the expression. Useful for implementing custom parsing logic.

Parameters
---------- ### expr

The expression to walk

BasicExpression<any> | null | undefined

### visitor

(node) => void

Visitor function called for each node

Returns
-------

void

Example
-------

typescript

walkExpression(whereExpr, (node) => {
  if (node.type === 'func' && node.name === 'eq') {
    console.log('Found equality comparison')
  }
})


walkExpression(whereExpr, (node) => {
  if (node.type === 'func' && node.name === 'eq') {
    console.log('Found equality comparison')
  }
})

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