title: how to pass a multi line json string in map in argo workflows
body: <p>I am working on creating a argo workflow with a loop <code>withParam</code> for map variable. In this map I want to use multi line json string. Is there any way to use it?</p>
  <p>Here is the way am using <code>policy</code> as multi line string but it is not working</p>
  <pre><code>apiVersion: argoproj.io/v1alpha1
  kind: Workflow
  metadata:
    generateName: loops-param-arg-
  spec:
    entrypoint: loop-param-arg-example
    arguments:
      parameters:
      - name: os-list
        value: |
          [
            { &quot;image&quot;: &quot;debian&quot;, &quot;tag&quot;: &quot;9.1&quot;, &quot;policy&quot;: &quot;{
                &quot;Version&quot;: &quot;2012-10-17&quot;,
                &quot;Statement&quot;: [
                    {
                        &quot;Sid&quot;: &quot;BucketAdmin&quot;,
                        &quot;Effect&quot;: &quot;Allow&quot;,
                        &quot;Principal&quot;: &quot;*&quot;,
                        &quot;Action&quot;: &quot;s3:*&quot;,
                        &quot;Resource&quot;: &quot;*&quot;
                    }
                ]
            }&quot; },
            { &quot;image&quot;: &quot;ubuntu&quot;, &quot;tag&quot;: &quot;17.10&quot;, &quot;policy&quot;:  &quot;{
                &quot;Version&quot;: &quot;2012-10-17&quot;,
                &quot;Statement&quot;: [
                    {
                        &quot;Sid&quot;: &quot;BucketAdmin&quot;,
                        &quot;Effect&quot;: &quot;Allow&quot;,
                        &quot;Principal&quot;: &quot;*&quot;,
                        &quot;Action&quot;: &quot;s3:*&quot;,
                        &quot;Resource&quot;: &quot;*&quot;
                    }
                ]
            }&quot;}
          ]
    templates:
    - name: loop-param-arg-example
      inputs:
        parameters:
        - name: os-list
      steps:
      - - name: test-linux
          template: cat-os-release
          arguments:
            parameters:
            - name: image
              value: &quot;{{item.image}}&quot;
            - name: tag
              value: &quot;{{item.tag}}&quot;
          withParam: &quot;{{inputs.parameters.os-list}}&quot;
  
    - name: cat-os-release
      inputs:
        parameters:
        - name: image
        - name: tag
      container:
        image: &quot;{{inputs.parameters.image}}:{{inputs.parameters.tag}} and policy is {{inputs.parameters.policy}}&quot;
        command: [cat]
        args: [/etc/os-release]
  </code></pre>
  <p>Is there any way in argo workflows to achieve this? if not, what's the alternate way to do this?</p>