JAVASCRIPT

comments in json

JSON does not support comments.

/* CSS/PHP/JS/SQL
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#Python
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how to comment in a json file

Sorry :3 no comments in JSON

how to comments in json file

{
	"_comment": "comment text goes here...",
    "name": "your-app-name",
    ...
}

json comments

JSON does not support comments.

HOWEVER, some popular .json files like (tsconfig, eslint, ...) allow comments
because the tools that use them deal with comments appropriatly.

why can i put comments in some json files

In some files the option for checking comments is off by default 
(tsconfig, tslint and eslint configs), as corresponding tools allow comments in
JSON (this is hardcoded). 

So IDEs recognize this and allow you to add comments even if standard 
doesnt allow.

Otherwise use:
{
	"_comment": "comment text goes here...",
    "name": "your-app-name",
    ...
}

Can comments be used in JSON?

No.

The JSON is data only, and if you include a comment, then it will be data too.

You could have a designated data element called "_comment" (or something) that should be ignored by apps that use the JSON data.

You would probably be better having the comment in the processes that generates/receives the JSON, as they are supposed to know what the JSON data will be in advance, or at least the structure of it.

But if you decided to:

{    "_comment": "comment text goes here...",    "glossary": {       "title": "example glossary",       "GlossDiv": {          "title": "S",          "GlossList": {             "GlossEntry": {                "ID": "SGML",                "SortAs": "SGML",                "GlossTerm": "Standard Generalized Markup Language",                "Acronym": "SGML",                "Abbrev": "ISO 8879:1986",                "GlossDef": {                   "para": "A meta-markup language, used to create markup languages such as DocBook.",                   "GlossSeeAlso": ["GML", "XML"]                },                "GlossSee": "markup"             }          }       }    } } 

Can comments be used in JSON?

No.
The JSON is data only, and if you include a comment, then it will be data too.
You could have a designated data element called "_comment" (or something) 
that should be ignored by apps that use the JSON data.
But if you decided to:
{
   "_comment": "comment text goes here...",
   "grocery": {
      "title": "Some title",
   }
}

Can comments be used in JSON ?

{
  "//": "Some browsers will use this to enable push notifications.",
  "//": "It is the same for all projects, this is not your project's sender ID",
  "gcm_sender_id": "1234567890"
}