How to Safely Use Write-Host with Colons in YAML Scripts

When writing scripts in YAML (such as for Azure DevOps pipelines), using colons : inside commands like Write-Host can sometimes trigger validation warnings in tools like Visual Studio.

This happens because YAML uses colons to define key-value pairs, and it may confuse your script as malformed YAML if colons aren't properly handled.

Here's how to avoid the issue:

✔️ Recommended Solutions

1. Use multi-line block with |
Best for longer scripts or when readability matters.

steps:
  - powershell: |
      Write-Host "Value is: 42"

2. Quote single-line scripts
Wrap the whole command in single or double quotes.

steps:
  - script: "Write-Host 'Value is: 42'"
    displayName: 'Print Value'

❌ Avoid this pattern:

steps:
  - script: Write-Host "Value is: 42"  # ❌ Unquoted colon — may cause YAML error