Method helper

packages/compiler-sfc/src/script/context.ts:68–71

(key: string)

  bindingMetadata: BindingMetadata = {}
  helperImports: Set<string> = new Set()
  helper(key: string): string {
    this.helperImports.add(key)
    return `_${key}`
  }

  /**
   * to be exposed on compiled script block for HMR cache busting