-`filename`_(default: null)_ - string to be used as a file path in
error/warning messages.
-`onWarning`_(default: null)_ - function to call on warning messages.
Loader will call this function with an instance of `YAMLException` for each warning.
-`schema` _(default: `DEFAULT_SAFE_SCHEMA`)_ - specifies a schema to use.
-`FAILSAFE_SCHEMA` - only strings, arrays and plain objects:
http://www.yaml.org/spec/1.2/spec.html#id2802346
-`JSON_SCHEMA` - all JSON-supported types:
http://www.yaml.org/spec/1.2/spec.html#id2803231
-`CORE_SCHEMA` - same as `JSON_SCHEMA`:
http://www.yaml.org/spec/1.2/spec.html#id2804923
-`DEFAULT_SAFE_SCHEMA` - all supported YAML types, without unsafe ones
(`!!js/undefined`, `!!js/regexp` and `!!js/function`):
http://yaml.org/type/
-`DEFAULT_FULL_SCHEMA` - all supported YAML types.
-`json`_(default: false)_ - compatibility with JSON.parse behaviour. If true, then duplicate keys in a mapping will override values rather than throwing an error.
NOTE: This function **does not** understand multi-document sources, it throws
exception on those.
NOTE: JS-YAML **does not** support schema-specific tag resolution restrictions.
So, the JSON schema is not as strictly defined in the YAML specification.
It allows numbers in any notation, use `Null` and `NULL` as `null`, etc.
The core schema also has no such restrictions. It allows binary notation for integers.
### load (string [ , options ])
**Use with care with untrusted sources**. The same as `safeLoad()` but uses
`DEFAULT_FULL_SCHEMA` by default - adds some JavaScript-specific types:
`!!js/function`, `!!js/regexp` and `!!js/undefined`. For untrusted sources, you
must additionally validate object structure to avoid injections:
Same as `safeLoadAll()` but uses `DEFAULT_FULL_SCHEMA` by default.
### safeDump (object [ , options ])
Serializes `object` as a YAML document. Uses `DEFAULT_SAFE_SCHEMA`, so it will
throw an exception if you try to dump regexps or functions. However, you can
disable exceptions by setting the `skipInvalid` option to `true`.
options:
-`indent`_(default: 2)_ - indentation width to use (in spaces).
-`noArrayIndent`_(default: false)_ - when true, will not add an indentation level to array elements
-`skipInvalid`_(default: false)_ - do not throw on invalid types (like function
in the safe schema) and skip pairs and single values with such types.
-`flowLevel` (default: -1) - specifies level of nesting, when to switch from
block to flow style for collections. -1 means block style everwhere
-`styles` - "tag" => "style" map. Each tag may have own set of styles.
-`schema` _(default: `DEFAULT_SAFE_SCHEMA`)_ specifies a schema to use.
-`sortKeys`_(default: `false`)_ - if `true`, sort keys when dumping YAML. If a
function, use the function to sort the keys.
-`lineWidth`_(default: `80`)_ - set max line width.
-`noRefs`_(default: `false`)_ - if `true`, don't convert duplicate objects into references
-`noCompatMode`_(default: `false`)_ - if `true` don't try to be compatible with older
yaml versions. Currently: don't quote "yes", "no" and so on, as required for YAML 1.1
-`condenseFlow`_(default: `false`)_ - if `true` flow sequences will be condensed, omitting the space between `a, b`. Eg. `'[a,b]'`, and omitting the space between `key: value` and quoting the key. Eg. `'{"a":b}'` Can be useful when using yaml for pretty URL query params as spaces are %-encoded.
The following table show availlable styles (e.g. "canonical",
"binary"...) available for each tag (.e.g. !!null, !!int ...). Yaml
output is shown on the right side after `=>` (default setting) or `->`:
``` none
!!null
"canonical" -> "~"
"lowercase" => "null"
"uppercase" -> "NULL"
"camelcase" -> "Null"
!!int
"binary" -> "0b1", "0b101010", "0b1110001111010"
"octal" -> "01", "052", "016172"
"decimal" => "1", "42", "7290"
"hexadecimal" -> "0x1", "0x2A", "0x1C7A"
!!bool
"lowercase" => "true", "false"
"uppercase" -> "TRUE", "FALSE"
"camelcase" -> "True", "False"
!!float
"lowercase" => ".nan", '.inf'
"uppercase" -> ".NAN", '.INF'
"camelcase" -> ".NaN", '.Inf'
```
Example:
``` javascript
safeDump (object, {
'styles': {
'!!null': 'canonical' // dump null as ~
},
'sortKeys': true // sort object keys
});
```
### dump (object [ , options ])
Same as `safeDump()` but without limits (uses `DEFAULT_FULL_SCHEMA` by default).
Supported YAML types
--------------------
The list of standard YAML tags and corresponding JavaScipt types. See also
[YAML tag discussion](http://pyyaml.org/wiki/YAMLTagDiscussion) and
[YAML types repository](http://yaml.org/type/).
```
!!null '' # null
!!bool 'yes' # bool
!!int '3...' # number
!!float '3.14...' # number
!!binary '...base64...' # buffer
!!timestamp 'YYYY-...' # date
!!omap [ ... ] # array of key-value pairs
!!pairs [ ... ] # array or array pairs
!!set { ... } # array of objects with given keys and null values
!!str '...' # string
!!seq [ ... ] # array
!!map { ... } # object
```
**JavaScript-specific tags**
```
!!js/regexp /pattern/gim # RegExp
!!js/undefined '' # Undefined
!!js/function 'function () {...}' # Function
```
Caveats
-------
Note, that you use arrays or objects as key in JS-YAML. JS does not allow objects
or arrays as keys, and stringifies (by calling `toString()` method) them at the
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