Function walk

Parameters

• node: AstNode

  initial node

• Optionalfilter: null | WalkerFilter

  control the walk process

• Optionalreverse: boolean

  walk in reverse order

  
  import {walk} from '@tbela99/css-parser';
  
  const css = `
  body { color:    color(from var(--base-color) display-p3 r calc(g + 0.24) calc(b + 0.15)); }
  
  html,
  body {
      line-height: 1.474;
  }
  
  .ruler {
  
      height: 10px;
  }
  `;
  
  for (const {node, parent, root} of walk(ast)) {
  
      // do something with node
  }
  Copy

  Using a filter function to control the ast traversal. the filter function returns a value of type WalkerOption.

  import {EnumToken, transform, walk, WalkerOptionEnum} from '@tbela99/css-parser';
  
  const css = `
  body { color:    color(from var(--base-color) display-p3 r calc(g + 0.24) calc(b + 0.15)); }
  
  html,
  body {
      line-height: 1.474;
  }
  
  .ruler {
  
      height: 10px;
  }
  `;
  
  function filter(node) {
  
      if (node.typ == EnumToken.AstRule && node.sel.includes('html')) {
  
          // skip the children of the current node
          return WalkerOptionEnum.IgnoreChildren;
      }
  }
  
  const result = await transform(css);
  for (const {node} of walk(result.ast, filter)) {
  
      console.error([EnumToken[node.typ]]);
  }
  
  // [ "StyleSheetNodeType" ]
  // [ "RuleNodeType" ]
  // [ "DeclarationNodeType" ]
  // [ "RuleNodeType" ]
  // [ "DeclarationNodeType" ]
  // [ "RuleNodeType" ]
  // [ "DeclarationNodeType" ]
  Copy