YAML strings value are quoted differently if the first character is a number.

[TristanCacqueray]

The context for this is https://github.com/dhall-lang/dhall-haskell/issues/1894 where I am wondering if a string value that contains a single word could always be quoted. This would enable a nicer output when the values are checksum, for example:

- checksum: "72b6ae7b4ed0"
- checksum: "e3c1b309d920"

Instead of the current output:

- checksum: "72b6ae7b4ed0"
- checksum: e3c1b309d920

Another odd behavior is regarding single vs double quote on this output:

ip: '127.0.0.1'
net: "127.0.0.1/8"

[patrickmn]

Hi @TristanCacqueray,

What to quote, when, and how, is very much a balancing act. We've gone back and forth many times (including on whether to quote single/simple words), and what we have now is the combination that seems the least upsetting.

I think going back to quoting single words to accommodate the checksum example would not be worth it, as it would make common outputs like this very hard to read:

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: foo
  name: "{{ .Release.Name }}-deployment"
spec:
  replicas: 1
  selector:
    matchLabels:
      app: foo
  template:
    metadata:
      labels:
        app: foo
      name: "{{ .Release.Name }}-pod"
    spec:
      containers:
        - command:
            - /data/bin/foo
            - "--port=7654"
          image: ubuntu:latest
          name: "{{ .Release.Name }}-container"
          ports:
            - containerPort: 7654
          script: |
            #!/bin/bash
            echo hello world
          volumeMounts:
            - mountPath: /data/mount1
              name: "{{ .Release.Name }}-volume-mount1"
            - mountPath: /data/mount2
              name: "{{ .Release.Name }}-volume-mount2"

Single words are specifically not quoted to make this kind of output look familiar.

The second example of an IP vs. IP/CIDR is an oddity, yeah. It's because we know it's safe to single-quote the first string, whereas the latter has symbols and we fall back to Aeson's encoding which is double-quoted. I would be happy to accept a PR that makes CIDR strings single-quoted so that those two are at least consistent.

Might I also suggest using encodeQuoted (quoted in https://hackage.haskell.org/package/dhall-json-1.7.0/docs/Dhall-JSON-Yaml.html#t:Options or --quoted in dhall-to-yaml)? That should make the quoting quite consistent.

[TristanCacqueray]

I agree the current status-quo is the least upsetting. I'll have a look to add a special case for IP/CIDR.

Thank you for the detailed feedback.