Maplibre GL JS number formatting snipped

maplibre-number-formatting.js

// Source https://osmus.slack.com/archives/C01G3D28DAB/p1706567778474359?thread_ts=1706534773.353969&cid=C01G3D28DAB

"text-field": [
  "let",
  "thousands",
  ["floor", ["/", ["get", "length_m"], 1000]],
  [
    "let",
    "reminder",
    [
      "to-string",
      ["-", ["get", "length_m"], ["*", ["var", "thousands"], 1000]]
    ],
    [
      "let",
      "part1",
      [
        "concat",
        ["slice", "000", ["length", ["var", "reminder"]]],
        ["var", "reminder"]
      ],
      [
        "case",
        [">", ["var", "thousands"], 0],
        [
          "concat",
          ["var", "thousands"],
          ",",
          ["var", "part1"],
          " km"
        ],
        ["concat", ["var", "reminder"], " km"]
      ]
    ]
  ]
]