example given in UG for addmenu command does not work

[nus-pe-script]

Describe the bug
Example given for the addmenu command in the User Guide does not work at all.

To Reproduce
Steps to reproduce the behavior:

1. Enter "addmenu Cheese Fries p/$3.50 type/sides t/New item"
2. Press ENTER key
3. See error: "Tag names should be alphanumeric"

Expected behavior
System adds the item "Cheese Fries" to the "sides" menu

Screenshots

Input entered:

Output seen:

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Reported by: @jeremyinelysium
Severity: Medium

_{[original: nusCS2113-AY1819S1/pe-1#147]}