Cannot get `where` to work on a JSON front matter list of words

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2

Do the same thing we discussed in your last topic:
https://discourse.gohugo.io/t/filter-an-array-of-ascii-words-based-on-word-length/40586

Front matter example

dictionary = ['APPLE','banana','cherry']
letterList = ['A','c']

Build an array of maps (words/letters normalized to lower case)

{{ $words := slice }}
{{ range .Params.dictionary }}
  {{ $words = $words | append (dict
    "word" (. | lower)
    "length" (. | len)
    "firstLetter" (substr . 0 1 | lower)
    "lastLetter" (substr . -1 | lower)
    )
  }}
{{ end }}

To visualize the resulting data structure you can do:

<pre>{{ jsonify (dict "indent" "  ") $words }}</pre>

It looks like this:

[
  {
    "firstLetter": "a",
    "lastLetter": "e",
    "length": 5,
    "word": "apple"
  },
  {
    "firstLetter": "b",
    "lastLetter": "a",
    "length": 6,
    "word": "banana"
  },
  {
    "firstLetter": "c",
    "lastLetter": "y",
    "length": 6,
    "word": "cherry"
  }
]

List words starting with…

{{ range $letter := .Params.letterList | sort }}
  {{ with where $words "firstLetter" "eq" (lower .) }}
    <p>Words starting with {{ $letter | upper }}</p>
    <ul>
      {{ range . }}
        <li>{{ .word }}</li>
      {{ end }}
    </ul>
  {{ end }}
{{ end }}

List words ending with…

{{ range $letter := .Params.letterList | sort }}
  {{ with where $words "lastLetter" "eq" (lower .) }}
    <p>Words ending with {{ $letter | upper }}</p>
    <ul>
      {{ range . }}
        <li>{{ .word }}</li>
      {{ end }}
    </ul>
  {{ end }}
{{ end }}