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https://github.com/drivly/yaml.fyi

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https://github.com/drivly/yaml.fyi

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README 

        
# YAML.FYI



### YAML is a data serialisation language designed to be directly writable and readable by humans.



It’s a strict superset of JSON, with the addition of syntactically significant newlines and indentation, like Python. Unlike Python, however, YAML doesn’t allow literal tab characters for indentation.



Here is the below YAML file:



And here is the YAML file converted to JSON:



```yaml

---  # document start



# Comments in YAML look like this.

# YAML support single-line comments.



################

# SCALAR TYPES #

################



# Our root object (which continues for the entire document) will be a map,

# which is equivalent to a dictionary, hash or object in other languages.

key: value

another_key: Another value goes here.

a_number_value: 100

scientific_notation: 1e+12

hex_notation: 0x123  # evaluates to 291

octal_notation: 0123 # evaluates to 83



# The number 1 will be interpreted as a number, not a boolean. 

# If you want it to be interpreted as a boolean, use true.

boolean: true

null_value: null

key with spaces: value



# Yes and No (doesn't matter the case) will be evaluated to boolean 

# true and false values respectively.

# To use the actual value use single or double quotes.

no: no            # evaluates to "false": false

yes: No           # evaluates to "true": false

not_enclosed: yes # evaluates to "not_enclosed": true

enclosed: "yes"   # evaluates to "enclosed": yes



# Notice that strings don't need to be quoted. However, they can be.

however: 'A string, enclosed in quotes.'

'Keys can be quoted too.': "Useful if you want to put a ':' in your key."

single quotes: 'have ''one'' escape pattern'

double quotes: "have many: \", \0, \t, \u263A, \x0d\x0a == \r\n, and more."

# UTF-8/16/32 characters need to be encoded

Superscript two: \u00B2



# Special characters must be enclosed in single or double quotes

special_characters: "[ John ] & { Jane } - "



# Multiple-line strings can be written either as a 'literal block' (using |), 

# or a 'folded block' (using '>').

# Literal block turn every newline within the string into a literal newline (\n).

# Folded block removes newlines within the string.

literal_block: |

  This entire block of text will be the value of the 'literal_block' key,

  with line breaks being preserved.



  The literal continues until de-dented, and the leading indentation is

  stripped.



      Any lines that are 'more-indented' keep the rest of their indentation -

      these lines will be indented by 4 spaces.

folded_style: >

  This entire block of text will be the value of 'folded_style', but this

  time, all newlines will be replaced with a single space.



  Blank lines, like above, are converted to a newline character.



      'More-indented' lines keep their newlines, too -

      this text will appear over two lines.



# |- and >- removes the trailing blank lines (also called literal/block "strip")

literal_strip: |-

  This entire block of text will be the value of the 'literal_block' key,

  with trailing blank line being stripped.

block_strip: >-

  This entire block of text will be the value of 'folded_style', but this

  time, all newlines will be replaced with a single space and 

  trailing blank line being stripped.



# |+ and >+ keeps trailing blank lines (also called literal/block "keep")

literal_keep: |+

  This entire block of text will be the value of the 'literal_block' key,

  with trailing blank line being kept.



block_keep: >+

  This entire block of text will be the value of 'folded_style', but this

  time, all newlines will be replaced with a single space and 

  trailing blank line being kept.



####################

# COLLECTION TYPES #

####################



# Nesting uses indentation. 2 space indent is preferred (but not required).

a_nested_map:

  key: value

  another_key: Another Value

  another_nested_map:

    hello: hello



# Maps don't have to have string keys.

0.25: a float key



# Keys can also be complex, like multi-line objects

# We use ? followed by a space to indicate the start of a complex key.

? |

  This is a key

  that has multiple lines

: and this is its value



# YAML also allows mapping between sequences with the complex key syntax

# Some language parsers might complain

# An example

? - Manchester United

  - Real Madrid

: [ 2001-01-01, 2002-02-02 ]



# Sequences (equivalent to lists or arrays) look like this

# (note that the '-' counts as indentation):

a_sequence:

  - Item 1

  - Item 2

  - 0.5  # sequences can contain disparate types.

  - Item 4

  - key: value

    another_key: another_value

  - - This is a sequence

    - inside another sequence

  - - - Nested sequence indicators

      - can be collapsed



# Since YAML is a superset of JSON, you can also write JSON-style maps and

# sequences:

json_map: { "key": "value" }

json_seq: [ 3, 2, 1, "takeoff" ]

and quotes are optional: { key: [ 3, 2, 1, takeoff ] }



#######################

# EXTRA YAML FEATURES #

#######################



# YAML also has a handy feature called 'anchors', which let you easily duplicate

# content across your document.

# Anchors identified by & character which define the value.

# Aliases identified by * character which acts as "see above" command.

# Both of these keys will have the same value:

anchored_content: &anchor_name This string will appear as the value of two keys.

other_anchor: *anchor_name



# Anchors can be used to duplicate/inherit properties

base: &base

  name: Everyone has same name



# The regexp << is called 'Merge Key Language-Independent Type'. It is used to

# indicate that all the keys of one or more specified maps should be inserted

# into the current map.

# NOTE: If key already exists alias will not be merged

foo:

  <<: *base # doesn't merge the anchor

  age: 10

  name: John

bar:

  <<: *base # base anchor will be merged

  age: 20



# foo and bar would also have name: Everyone has same name



# YAML also has tags, which you can use to explicitly declare types.

# Syntax: !![typeName] [value]

explicit_boolean: !!bool true

explicit_integer: !!int 42

explicit_float: !!float -42.24

explicit_string: !!str 0.5

explicit_datetime: !!timestamp 2022-11-17 12:34:56.78 +9

explicit_null: !!null null



# Some parsers implement language specific tags, like this one for Python's

# complex number type.

python_complex_number: !!python/complex 1+2j



# We can also use yaml complex keys with language specific tags

? !!python/tuple [ 5, 7 ]

: Fifty Seven

# Would be {(5, 7): 'Fifty Seven'} in Python



####################

# EXTRA YAML TYPES #

####################



# Strings and numbers aren't the only scalars that YAML can understand.

# ISO-formatted date and datetime literals are also parsed.

datetime_canonical: 2001-12-15T02:59:43.1Z

datetime_space_seperated_with_time_zone: 2001-12-14 21:59:43.10 -5

date_implicit: 2002-12-14

date_explicit: !!timestamp 2002-12-14



# The !!binary tag indicates that a string is actually a base64-encoded

# representation of a binary blob.

gif_file: !!binary |

  R0lGODlhDAAMAIQAAP//9/X17unp5WZmZgAAAOfn515eXvPz7Y6OjuDg4J+fn5

  OTk6enp56enmlpaWNjY6Ojo4SEhP/++f/++f/++f/++f/++f/++f/++f/++f/+

  +f/++f/++f/++f/++f/++SH+Dk1hZGUgd2l0aCBHSU1QACwAAAAADAAMAAAFLC

  AgjoEwnuNAFOhpEMTRiggcz4BNJHrv/zCFcLiwMWYNG84BwwEeECcgggoBADs=



# YAML also has a set type, which looks like this:

set:

  ? item1

  ? item2

  ? item3

or: { item1, item2, item3 }



# Sets are just maps with null values; the above is equivalent to:

set2:

  item1: null

  item2: null

  item3: null



...  # document end

```