yaml value

The yaml value type represents a YAML value. This can be any of the following:

Null: Represented as null, ~ or with no value at all (i.e. leaving a key value empty)
Boolean: Represented as true or false
Integer: an integer number.
Floating Point: a floating-point number, written in a human-readable format, with a dot separating the fractional part.
String: A Unicode string. YAML supports single-quoted, double-quoted, or unquoted strings. Escaping is done with backslashes in double-quoted strings. An empty string (e.g. '') is different from Null.
Array (Sequence): A sequence of values, represented as a list with each item prefixed by a dash - and aligned at the same indentation level. The values do not need to be of the same type.
Object (Mapping): A collection of key-value pairs, where keys are strings and values can be any valid YAML value. These mappings are separated by a colon : and structured using indentation to denote hierarchy. Keys must be unique within a mapping.

In our implementation, we use our own definitions of the terms "key" and "value".

We store the entire "YAML object" in a yaml value. Each key-value pair inside it is a yaml key. The "key" in a key-value pair is just a string and we refer to it as the "name of the key". The "value" in a key-value pair is another yaml value.

Our YAML parser is implemented using the yaml-cpp library, available at https://github.com/jbeder/yaml-cpp.

For more information, see the YAML key page.

Creation
Properties
Casts
Operators

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

Creation

value of <yaml key> : yaml value

Returns the value of the key-value pair.

Q: values of keys of yaml of "{a: 1, b: 2}"
A: 1
A: 2

Plural: values

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

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yaml of <file> : yaml value

Returns a YAML value for the content of the file.

The following is the content of a test file named "test.yaml".

published: true
domain:
  - devops
  - devsecops
tutorial:
  - yaml:
      name: YAML Ain't Markup Language
      type: awesome
      born: 2001
  - xml:
      name: Extensible Markup Language
      type: good
      born: 1996

This example shows how to create a yaml value representing the content of the file "test.yaml". Note that newline \n characters have been "percent-encoded" as %0a.

Q: yaml of file "./test.yaml"
A: domain:%0a - devops%0a - devsecops%0apublished: true%0atutorial:%0a - yaml:%0a name: YAML Ain't Markup Language%0a type: awesome%0a born: 2001%0a - xml:%0a name: Extensible Markup Language%0a type: good%0a born: 1996

The following is the content of a test file named "complex.yaml".

my_boolean: true
my_number: 3
my_float: 3.14
my_string_1: "foo bar"
my-string-2: foo bar
my_list_1:
  - A
  - B
my-list-2: ['A', 'B']
my_dict_1:
  field_a: A
  field_b: B
  sub_dict:
    sub_field: C1
my-dict-2: { field_a: A, field_b: B, sub_dict: { sub_field: C1 } }
my_obj_list_1:
  -
    obj_1_field: 1A
  -
    obj_2_field: 2A
my-obj-list-2: [ { obj_1_field: 1A }, { obj_2_field: 2A } ]

This example shows how to create a yaml value representing the content of the file "complex.yaml". Note that certain characters have been "percent-encoded".

Q: yaml of file "./complex.yaml"
A: my_dict_1:%0a field_a: A%0a field_b: B%0a sub_dict:%0a sub_field: C1%0amy_list_1:%0a - A%0a - B%0amy-string-2: foo bar%0amy_boolean: true%0amy_string_1: foo bar%0amy_number: 3%0amy_float: 3.14%0amy-list-2: [A, B]%0amy-dict-2:%0a field_a: A%0a field_b: B%0a sub_dict:%0a sub_field: C1%0amy_obj_list_1:%0a - obj_1_field: 1A%0a - obj_2_field: 2A%0amy-obj-list-2: [{obj_1_field: 1A}, {obj_2_field: 2A}]

Plural: yamls

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

yaml of <string> : yaml value

Returns a YAML object for the string.

The following is the content of a test file named "test.yaml".

published: true
domain:
  - devops
  - devsecops
tutorial:
  - yaml:
      name: YAML Ain't Markup Language
      type: awesome
      born: 2001
  - xml:
      name: Extensible Markup Language
      type: good
      born: 1996

This example shows how to create a yaml value representing the content of the file "test.yaml" turned into a string. Note that newline \n characters have been "percent-encoded" as %0a.

Q: yaml of "published: true%0adomain:%0a - devops%0a - devsecops%0atutorial:%0a - yaml:%0a name: YAML Ain't Markup Language%0a type: awesome%0a born: 2001%0a - xml:%0a name: Extensible Markup Language%0a type: good%0a born: 1996"
A: domain:%0a - devops%0a - devsecops%0apublished: true%0atutorial:%0a - yaml:%0a name: YAML Ain't Markup Language%0a type: awesome%0a born: 2001%0a - xml:%0a name: Extensible Markup Language%0a type: good%0a born: 1996

The following is the content of a test file named "complex.yaml".

my_boolean: true
my_number: 3
my_float: 3.14
my_string_1: "foo bar"
my-string-2: foo bar
my_list_1:
  - A
  - B
my-list-2: ['A', 'B']
my_dict_1:
  field_a: A
  field_b: B
  sub_dict:
    sub_field: C1
my-dict-2: { field_a: A, field_b: B, sub_dict: { sub_field: C1 } }
my_obj_list_1:
  -
    obj_1_field: 1A
  -
    obj_2_field: 2A
my-obj-list-2: [ { obj_1_field: 1A }, { obj_2_field: 2A } ]

This example shows how to create a yaml value representing the content of the file "complex.yaml" turned into a string. Note that certain characters have been "percent-encoded".

Q: yaml of "my_boolean: true%0amy_number: 3%0amy_float: 3.14%0amy_string_1: %22foo bar%22%0amy-string-2: foo bar%0amy_list_1:%0a - A%0a - B%0amy-list-2: ['A', 'B']%0amy_dict_1:%0a field_a: A%0a field_b: B%0a sub_dict:%0a sub_field: C1%0amy-dict-2: { field_a: A, field_b: B, sub_dict: { sub_field: C1 } }%0amy_obj_list_1:%0a -%0a obj_1_field: 1A%0a -%0a obj_2_field: 2A%0amy-obj-list-2: [ { obj_1_field: 1A }, { obj_2_field: 2A } ]"
A: my_dict_1:%0a field_a: A%0a field_b: B%0a sub_dict:%0a sub_field: C1%0amy_list_1:%0a - A%0a - B%0amy-string-2: foo bar%0amy_boolean: true%0amy_string_1: foo bar%0amy_number: 3%0amy_float: 3.14%0amy-list-2: [A, B]%0amy-dict-2:%0a field_a: A%0a field_b: B%0a sub_dict:%0a sub_field: C1%0amy_obj_list_1:%0a - obj_1_field: 1A%0a - obj_2_field: 2A%0amy-obj-list-2: [{obj_1_field: 1A}, {obj_2_field: 2A}]

Plural: yamls

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

Properties

element <integer> of <yaml value> : yaml value

Returns the nth value in a YAML array.

Q: element 2 of yaml of "[a, b, c, d]"
A: c

Plural: elements

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

element of <yaml value> : yaml value

Returns each value in a YAML array.

Q: elements of yaml of "[1, 2, 3]"
A: 1
A: 2
A: 3

Plural: elements

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

key <string> of <yaml value> : yaml key

Returns the key-value pair corresponding to the specified key, in a YAML object.

Q: value of key "abc" of yaml of "abc: 123"
A: 123

Plural: keys

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Session, Solaris, Ubuntu, Windows

permalink source

key of <yaml value> : yaml key

Returns all key-value pairs in a YAML object.

Q: keys of yaml of "{a: 1, b: 2}"
A: a : 1
A: b : 2

Plural: keys

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

path <string> of <yaml value> : yaml value

Returns a yaml value object representing the data retrieved by the specified YAMLPath expression.

YAML path expressions can use the "dot notation" or the "bracket notation". The bracket notation is useful for accessing keys that include special characters, such as the period and space, which cannot be expressed with the dot-notation. To escape a character, use '\' before it.

Example of YAML path using the dot notation.

Q: path "$.domain[0]" of yaml of file "./test.yaml"
A: devops

Example of YAML path using the bracket notation.

Q: path "$['tutorial'][0]['yaml']['name']" of yaml of file "./test.yaml"
A: YAML Ain't Markup Language

Example of YAML path using the bracket notation and an escaped quote character.

Q: path "$['Steve\'s iPhone']" of yaml of "{ %22Steve's iPhone%22 : 4 }"
A: 4

Plural: paths

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

type of <yaml value> : string

Returns the type of data stored in the yaml value object. It outputs one of the following strings:

yaml boolean
yaml float
yaml integer
yaml mapping
yaml null
yaml sequence
yaml string

Q: type of yaml of "{a: [a, b, c, d]}"
A: YAML Map

Plural: types

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

Casts

<yaml value> as boolean : boolean

Casts a YAML value as a boolean. The value type must be boolean.

Q: yaml of "true" as boolean
A: True

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

<yaml value> as float : floating point

Casts a YAML value as a float. The value type must be float.

Q: yaml of "3.14" as float
A: 3.14000010490417

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

<yaml value> as integer : integer

Casts a YAML value as an integer. The value type must be integer.

Q: yaml of "1" as integer
A: 1

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

<yaml value> as string : string

Returns a string representation of the YAML value.

Q: yaml of "name" as string
A: name

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source

Operators

<yaml value> = <yaml value> : boolean

Returns whether the YAML values are equal. When comparing two YAML arrays, this operator will only yield true if they contain the same elements in the same order. When comparing two YAML objects, this operator will yield true if they contain the same key-value pairs, regardless of their order.

This example shows the operator used to compare two YAML arrays.

Q: yaml value of "key1: [a1, a2, a3]" = yaml of "key1: [a1, a2, a3]"
A: True

This example shows the operator used to compare two YAML objects.

Q: yaml of "{Bacon:Cheeseburger, Brazilian:Steak}" = yaml of "{Brazilian:Steak, Bacon:Cheeseburger}"
A: True

Version	Platforms
11.0.5.0	AIX, Debian, Mac, Raspbian, Red Hat, SUSE, Solaris, Ubuntu, Windows

permalink source