Fixing docs

pkg/yqlib/doc/Assign.md

@@ -5,8 +5,7 @@ Which will assign the LHS node values to the RHS node values. The RHS expression
 
 ### relative form: `|=`
 This will do a similar thing to the plain form, however, the RHS expression is run against _the LHS nodes_. This is useful for updating values based on old values, e.g. increment.
-## Examples
+## Update node to be the child value
-### Update node to be the child value
 Given a sample.yml file of:
 ```yaml
 a:
@@ -23,7 +22,7 @@ a:
   g: foof
 ```
 
-### Update node to be the sibling value
+## Update node to be the sibling value
 Given a sample.yml file of:
 ```yaml
 a:
@@ -40,7 +39,7 @@ a: sibling
 b: sibling
 ```
 
-### Updated multiple paths
+## Updated multiple paths
 Given a sample.yml file of:
 ```yaml
 a: fieldA
@@ -58,7 +57,7 @@ b: fieldB
 c: potatoe
 ```
 
-### Update string value
+## Update string value
 Given a sample.yml file of:
 ```yaml
 a:
@@ -74,7 +73,7 @@ a:
   b: frog
 ```
 
-### Update string value via |=
+## Update string value via |=
 Note there is no difference between `=` and `|=` when the RHS is a scalar
 
 Given a sample.yml file of:
@@ -92,7 +91,7 @@ a:
   b: frog
 ```
 
-### Update selected results
+## Update selected results
 Given a sample.yml file of:
 ```yaml
 a:
@@ -110,7 +109,7 @@ a:
   c: cactus
 ```
 
-### Update array values
+## Update array values
 Given a sample.yml file of:
 ```yaml
 - candy
@@ -128,10 +127,10 @@ will output
 - bogs
 ```
 
-### Update empty object
+## Update empty object
 Given a sample.yml file of:
 ```yaml
-'': null
+{}
 ```
 then
 ```bash
@@ -139,15 +138,13 @@ yq eval '.a.b |= "bogs"' sample.yml
 ```
 will output
 ```yaml
-'': null
+{a: {b: bogs}}
-a:
-  b: bogs
 ```
 
-### Update empty object and array
+## Update empty object and array
 Given a sample.yml file of:
 ```yaml
-'': null
+{}
 ```
 then
 ```bash
@@ -155,9 +152,6 @@ yq eval '.a.b[0] |= "bogs"' sample.yml
 ```
 will output
 ```yaml
-'': null
+{a: {b: [bogs]}}
-a:
-  b:
-    - bogs
 ```
 

pkg/yqlib/doc/Boolean Operators.md

@@ -1,6 +1,5 @@
-The `or` and `and` operators take two parameters and return a boolean result. These are most commonly used with the `select` operator to filter particular nodes.
+The `or` and `and` operators take two parameters and return a boolean result. `not` flips a boolean from true to false, or vice versa. These are most commonly used with the `select` operator to filter particular nodes.
-## Examples
+## OR example
-### OR example
 Running
 ```bash
 yq eval --null-input 'true or false'
@@ -10,7 +9,7 @@ will output
 true
 ```
 
-### AND example
+## AND example
 Running
 ```bash
 yq eval --null-input 'true and false'
@@ -20,7 +19,7 @@ will output
 false
 ```
 
-### Matching nodes with select, equals and or
+## Matching nodes with select, equals and or
 Given a sample.yml file of:
 ```yaml
 - a: bird
@@ -42,3 +41,73 @@ will output
   b: fly
 ```
 
+## Not true is false
+Running
+```bash
+yq eval --null-input 'true | not'
+```
+will output
+```yaml
+false
+```
+
+## Not false is true
+Running
+```bash
+yq eval --null-input 'false | not'
+```
+will output
+```yaml
+true
+```
+
+## String values considered to be true
+Running
+```bash
+yq eval --null-input '"cat" | not'
+```
+will output
+```yaml
+false
+```
+
+## Empty string value considered to be true
+Running
+```bash
+yq eval --null-input '"" | not'
+```
+will output
+```yaml
+false
+```
+
+## Numbers are considered to be true
+Running
+```bash
+yq eval --null-input '1 | not'
+```
+will output
+```yaml
+false
+```
+
+## Zero is considered to be true
+Running
+```bash
+yq eval --null-input '0 | not'
+```
+will output
+```yaml
+false
+```
+
+## Null is considered to be false
+Running
+```bash
+yq eval --null-input '~ | not'
+```
+will output
+```yaml
+true
+```
+

pkg/yqlib/doc/Collect into Array.md

@@ -3,8 +3,7 @@
 This creates an array using the expression between the square brackets.
 
 
-## Examples
+## Collect empty
-### Collect empty
 Running
 ```bash
 yq eval --null-input '[]'
@@ -13,7 +12,7 @@ will output
 ```yaml
 ```
 
-### Collect single
+## Collect single
 Running
 ```bash
 yq eval --null-input '["cat"]'
@@ -23,7 +22,7 @@ will output
 - cat
 ```
 
-### Collect many
+## Collect many
 Given a sample.yml file of:
 ```yaml
 a: cat

pkg/yqlib/doc/Collect into Object.md

@@ -1,15 +1,15 @@
 This is used to construct objects (or maps). This can be used against existing yaml, or to create fresh yaml documents.
-## Examples
+## Collect empty object
-### Collect empty object
 Running
 ```bash
 yq eval --null-input '{}'
 ```
 will output
 ```yaml
+{}
 ```
 
-### Wrap (prefix) existing object
+## Wrap (prefix) existing object
 Given a sample.yml file of:
 ```yaml
 name: Mike
@@ -24,7 +24,7 @@ wrap:
   name: Mike
 ```
 
-### Using splat to create multiple objects
+## Using splat to create multiple objects
 Given a sample.yml file of:
 ```yaml
 name: Mike
@@ -42,7 +42,7 @@ Mike: cat
 Mike: dog
 ```
 
-### Working with multiple documents
+## Working with multiple documents
 Given a sample.yml file of:
 ```yaml
 name: Mike
@@ -67,7 +67,7 @@ Rosey: monkey
 Rosey: sheep
 ```
 
-### Creating yaml from scratch
+## Creating yaml from scratch
 Running
 ```bash
 yq eval --null-input '{"wrap": "frog"}'

pkg/yqlib/doc/Comment Operators.md

@@ -1,6 +1,5 @@
 Use these comment operators to set or retrieve comments.
-## Examples
+## Set line comment
-### Set line comment
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -14,7 +13,7 @@ will output
 a: cat # single
 ```
 
-### Set head comment
+## Set head comment
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -30,7 +29,7 @@ will output
 a: cat
 ```
 
-### Set foot comment, using an expression
+## Set foot comment, using an expression
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -46,7 +45,7 @@ a: cat
 # cat
 ```
 
-### Remove comment
+## Remove comment
 Given a sample.yml file of:
 ```yaml
 a: cat # comment
@@ -62,7 +61,7 @@ a: cat
 b: dog # leave this
 ```
 
-### Remove all comments
+## Remove all comments
 Given a sample.yml file of:
 ```yaml
 a: cat # comment
@@ -76,7 +75,7 @@ will output
 a: cat
 ```
 
-### Get line comment
+## Get line comment
 Given a sample.yml file of:
 ```yaml
 a: cat # meow
@@ -90,7 +89,7 @@ will output
 meow
 ```
 
-### Get head comment
+## Get head comment
 Given a sample.yml file of:
 ```yaml
 a: cat # meow
@@ -104,7 +103,7 @@ will output
 
 ```
 
-### Get foot comment
+## Get foot comment
 Given a sample.yml file of:
 ```yaml
 a: cat # meow

pkg/yqlib/doc/Delete.md

@@ -1,6 +1,5 @@
 Deletes matching entries in maps or arrays.
-## Examples
+## Delete entry in map
-### Delete entry in map
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -15,7 +14,7 @@ will output
 a: cat
 ```
 
-### Delete entry in array
+## Delete entry in array
 Given a sample.yml file of:
 ```yaml
 - 1
@@ -32,7 +31,7 @@ will output
 - 3
 ```
 
-### Delete no matches
+## Delete no matches
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -48,7 +47,7 @@ a: cat
 b: dog
 ```
 
-### Delete matching entries
+## Delete matching entries
 Given a sample.yml file of:
 ```yaml
 a: cat

pkg/yqlib/doc/Document Index Operator.md

@@ -1,6 +1,4 @@
-
+## Retrieve a document index
-## Examples
-### Retrieve a document index
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -18,7 +16,7 @@ will output
 1
 ```
 
-### Filter by document index
+## Filter by document index
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -34,7 +32,7 @@ will output
 a: frog
 ```
 
-### Print Document Index with matches
+## Print Document Index with matches
 Given a sample.yml file of:
 ```yaml
 a: cat

pkg/yqlib/doc/Document Index.md

@@ -0,0 +1,54 @@
+Use the `documentIndex` operator to select nodes of a particular document.
+## Retrieve a document index
+Given a sample.yml file of:
+```yaml
+a: cat
+---
+a: frog
+```
+then
+```bash
+yq eval '.a | documentIndex' sample.yml
+```
+will output
+```yaml
+0
+---
+1
+```
+
+## Filter by document index
+Given a sample.yml file of:
+```yaml
+a: cat
+---
+a: frog
+```
+then
+```bash
+yq eval 'select(. | documentIndex == 1)' sample.yml
+```
+will output
+```yaml
+a: frog
+```
+
+## Print Document Index with matches
+Given a sample.yml file of:
+```yaml
+a: cat
+---
+a: frog
+```
+then
+```bash
+yq eval '.a | ({"match": ., "doc": (. | documentIndex)})' sample.yml
+```
+will output
+```yaml
+match: cat
+doc: 0
+match: frog
+doc: 1
+```
+

pkg/yqlib/doc/Equals.md

@@ -1,5 +1,3 @@
-## Equals Operator
-
 This is a boolean operator that will return ```true``` if the LHS is equal to the RHS and ``false`` otherwise.
 
 ```
@@ -13,8 +11,7 @@ select(.a == .b)
 ```
 
 
-## Examples
+## Match string
-### Match string
 Given a sample.yml file of:
 ```yaml
 - cat
@@ -32,7 +29,7 @@ true
 false
 ```
 
-### Match number
+## Match number
 Given a sample.yml file of:
 ```yaml
 - 3
@@ -50,7 +47,7 @@ true
 false
 ```
 
-### Match nulls
+## Match nulls
 Running
 ```bash
 yq eval --null-input 'null == ~'

pkg/yqlib/doc/Explode.md

@@ -1,6 +1,5 @@
 Explodes (or dereferences) aliases and anchors.
-## Examples
+## Explode alias and anchor
-### Explode alias and anchor
 Given a sample.yml file of:
 ```yaml
 f:
@@ -18,7 +17,7 @@ f:
   b: cat
 ```
 
-### Explode with no aliases or anchors
+## Explode with no aliases or anchors
 Given a sample.yml file of:
 ```yaml
 a: mike
@@ -32,7 +31,7 @@ will output
 a: mike
 ```
 
-### Explode with alias keys
+## Explode with alias keys
 Given a sample.yml file of:
 ```yaml
 f:
@@ -50,7 +49,7 @@ f:
   cat: b
 ```
 
-### Explode with merge anchors
+## Explode with merge anchors
 Given a sample.yml file of:
 ```yaml
 foo: &foo

pkg/yqlib/doc/File Operators.md

@@ -1,10 +1,11 @@
 File operators are most often used with merge when needing to merge specific files together. Note that when doing this, you will need to use `eval-all` to ensure all yaml documents are loaded into memory before performing the merge (as opposed to `eval` which runs the expression once per document).
 
+## Merging files
+Note the use of eval-all to ensure all documents are loaded into memory.
 ```bash
 yq eval-all 'select(fileIndex == 0) * select(filename == "file2.yaml")' file1.yaml file2.yaml
 ```
-## Examples
+## Get filename
-### Get filename
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -18,7 +19,7 @@ will output
 sample.yaml
 ```
 
-### Get file index
+## Get file index
 Given a sample.yml file of:
 ```yaml
 a: cat

pkg/yqlib/doc/Mulitply Operator.md

@@ -1,121 +0,0 @@
-# Mulitply Operator
-## Examples
-### Merge objects together
-sample.yml:
-```yaml
-{a: {also: me}, b: {also: {g: wizz}}}
-```
-Expression
-```bash
-yq '. * {"a":.b}' < sample.yml
-```
-Result
-```yaml
-{a: {also: {g: wizz}}, b: {also: {g: wizz}}}
-```
-### Merge keeps style of LHS
-sample.yml:
-```yaml
-a: {things: great}
-b:
-  also: "me"
-
-```
-Expression
-```bash
-yq '. * {"a":.b}' < sample.yml
-```
-Result
-```yaml
-a: {things: great, also: "me"}
-b:
-  also: "me"
-```
-### Merge arrays
-sample.yml:
-```yaml
-{a: [1,2,3], b: [3,4,5]}
-```
-Expression
-```bash
-yq '. * {"a":.b}' < sample.yml
-```
-Result
-```yaml
-{a: [3, 4, 5], b: [3, 4, 5]}
-```
-### Merge to prefix an element
-sample.yml:
-```yaml
-{a: cat, b: dog}
-```
-Expression
-```bash
-yq '. * {"a": {"c": .a}}' < sample.yml
-```
-Result
-```yaml
-{a: {c: cat}, b: dog}
-```
-### Merge with simple aliases
-sample.yml:
-```yaml
-{a: &cat {c: frog}, b: {f: *cat}, c: {g: thongs}}
-```
-Expression
-```bash
-yq '.c * .b' < sample.yml
-```
-Result
-```yaml
-{g: thongs, f: *cat}
-```
-### Merge does not copy anchor names
-sample.yml:
-```yaml
-{a: {c: &cat frog}, b: {f: *cat}, c: {g: thongs}}
-```
-Expression
-```bash
-yq '.c * .a' < sample.yml
-```
-Result
-```yaml
-{g: thongs, c: frog}
-```
-### Merge with merge anchors
-sample.yml:
-```yaml
-
-foo: &foo
-  a: foo_a
-  thing: foo_thing
-  c: foo_c
-
-bar: &bar
-  b: bar_b
-  thing: bar_thing
-  c: bar_c
-
-foobarList:
-  b: foobarList_b
-  <<: [*foo,*bar]
-  c: foobarList_c
-
-foobar:
-  c: foobar_c
-  <<: *foo
-  thing: foobar_thing
-
-```
-Expression
-```bash
-yq '.foobar * .foobarList' < sample.yml
-```
-Result
-```yaml
-c: foobarList_c
-<<: [*foo, *bar]
-thing: foobar_thing
-b: foobarList_b
-```

pkg/yqlib/doc/Multiply.md

@@ -3,8 +3,15 @@ Like the multiple operator in `jq`, depending on the operands, this multiply ope
 Upcoming versions of `yq` will add support for other types of multiplication (numbers, strings).
 
 Note that when merging objects, this operator returns the merged object (not the parent). This will be clearer in the examples below.
-## Examples
+
-### Merge objects together, returning merged result only
+## Merging files
+Note the use of eval-all to ensure all documents are loaded into memory.
+
+```bash
+yq eval-all 'select(fileIndex == 0) * select(fileIndex == 1)' file1.yaml file2.yaml
+```
+
+## Merge objects together, returning merged result only
 Given a sample.yml file of:
 ```yaml
 a:
@@ -27,7 +34,7 @@ fieldA: cat
 fieldB: dog
 ```
 
-### Merge objects together, returning parent object
+## Merge objects together, returning parent object
 Given a sample.yml file of:
 ```yaml
 a:
@@ -55,12 +62,13 @@ b:
   fieldB: dog
 ```
 
-### Merge keeps style of LHS
+## Merge keeps style of LHS
 Given a sample.yml file of:
 ```yaml
 a: {things: great}
 b:
   also: "me"
+
 ```
 then
 ```bash
@@ -73,7 +81,7 @@ b:
   also: "me"
 ```
 
-### Merge arrays
+## Merge arrays
 Given a sample.yml file of:
 ```yaml
 a:
@@ -101,7 +109,7 @@ b:
   - 5
 ```
 
-### Merge to prefix an element
+## Merge to prefix an element
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -118,7 +126,7 @@ a:
 b: dog
 ```
 
-### Merge with simple aliases
+## Merge with simple aliases
 Given a sample.yml file of:
 ```yaml
 a: &cat
@@ -138,7 +146,7 @@ g: thongs
 f: *cat
 ```
 
-### Merge does not copy anchor names
+## Merge does not copy anchor names
 Given a sample.yml file of:
 ```yaml
 a:
@@ -158,7 +166,7 @@ g: thongs
 c: frog
 ```
 
-### Merge with merge anchors
+## Merge with merge anchors
 Given a sample.yml file of:
 ```yaml
 foo: &foo

pkg/yqlib/doc/Not Operator.md

@@ -1,72 +0,0 @@
-This is a boolean operator and will return `true` when given a `false` value (including null), and `false` otherwise.
-## Examples
-### Not true is false
-Running
-```bash
-yq eval --null-input 'true | not'
-```
-will output
-```yaml
-false
-```
-
-### Not false is true
-Running
-```bash
-yq eval --null-input 'false | not'
-```
-will output
-```yaml
-true
-```
-
-### String values considered to be true
-Running
-```bash
-yq eval --null-input '"cat" | not'
-```
-will output
-```yaml
-false
-```
-
-### Empty string value considered to be true
-Running
-```bash
-yq eval --null-input '"" | not'
-```
-will output
-```yaml
-false
-```
-
-### Numbers are considered to be true
-Running
-```bash
-yq eval --null-input '1 | not'
-```
-will output
-```yaml
-false
-```
-
-### Zero is considered to be true
-Running
-```bash
-yq eval --null-input '0 | not'
-```
-will output
-```yaml
-false
-```
-
-### Null is considered to be false
-Running
-```bash
-yq eval --null-input '~ | not'
-```
-will output
-```yaml
-true
-```
-

pkg/yqlib/doc/Path.md

@@ -1,6 +1,5 @@
-The path operator can be used to find the traversal paths of matching nodes in an expression. The path is returned as an array, which if traversed in order will lead to the matching node.
+The path operator can be used to get the traversal paths of matching nodes in an expression. The path is returned as an array, which if traversed in order will lead to the matching node.
-## Examples
+## Map path
-### Map path
 Given a sample.yml file of:
 ```yaml
 a:
@@ -16,7 +15,7 @@ will output
 - b
 ```
 
-### Array path
+## Array path
 Given a sample.yml file of:
 ```yaml
 a:
@@ -33,7 +32,7 @@ will output
 - 1
 ```
 
-### Print path and value
+## Print path and value
 Given a sample.yml file of:
 ```yaml
 a:

pkg/yqlib/doc/Recursive Descent.md

@@ -3,69 +3,7 @@ This operator recursively matches all children nodes given of a particular eleme
 ```bash
 yq eval '.. style= "flow"' file.yaml
 ```
-## Examples
+## Aliases are not traversed
-### Map
-Given a sample.yml file of:
-```yaml
-a:
-  b: apple
-```
-then
-```bash
-yq eval '..' sample.yml
-```
-will output
-```yaml
-a:
-  b: apple
-b: apple
-apple
-```
-
-### Array
-Given a sample.yml file of:
-```yaml
-- 1
-- 2
-- 3
-```
-then
-```bash
-yq eval '..' sample.yml
-```
-will output
-```yaml
-- 1
-- 2
-- 3
-1
-2
-3
-```
-
-### Array of maps
-Given a sample.yml file of:
-```yaml
-- a: cat
-- 2
-- true
-```
-then
-```bash
-yq eval '..' sample.yml
-```
-will output
-```yaml
-- a: cat
-- 2
-- true
-a: cat
-cat
-2
-true
-```
-
-### Aliases are not traversed
 Given a sample.yml file of:
 ```yaml
 a: &cat
@@ -74,20 +12,20 @@ b: *cat
 ```
 then
 ```bash
-yq eval '..' sample.yml
+yq eval '[..]' sample.yml
 ```
 will output
 ```yaml
-a: &cat
+- a: &cat
     c: frog
   b: *cat
-&cat
+- &cat
   c: frog
-frog
+- frog
-*cat
+- *cat
 ```
 
-### Merge docs are not traversed
+## Merge docs are not traversed
 Given a sample.yml file of:
 ```yaml
 foo: &foo
@@ -111,15 +49,15 @@ foobar:
 ```
 then
 ```bash
-yq eval '.foobar | ..' sample.yml
+yq eval '.foobar | [..]' sample.yml
 ```
 will output
 ```yaml
-c: foobar_c
+- c: foobar_c
   !!merge <<: *foo
   thing: foobar_thing
-foobar_c
+- foobar_c
-*foo
+- *foo
-foobar_thing
+- foobar_thing
 ```
 

pkg/yqlib/doc/Select.md

@@ -1,6 +1,5 @@
 Select is used to filter arrays and maps by a boolean expression.
-## Examples
+## Select elements from array
-### Select elements from array
 Given a sample.yml file of:
 ```yaml
 - cat
@@ -17,7 +16,7 @@ cat
 goat
 ```
 
-### Select and update matching values in map
+## Select and update matching values in map
 Given a sample.yml file of:
 ```yaml
 a:

pkg/yqlib/doc/Style.md

@@ -1,6 +1,5 @@
 The style operator can be used to get or set the style of nodes (e.g. string style, yaml style)
-## Examples
+## Set tagged style
-### Set tagged style
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -21,7 +20,7 @@ c: !!float 3.2
 e: !!bool true
 ```
 
-### Set double quote style
+## Set double quote style
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -41,7 +40,7 @@ c: "3.2"
 e: "true"
 ```
 
-### Set single quote style
+## Set single quote style
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -61,7 +60,7 @@ c: '3.2'
 e: 'true'
 ```
 
-### Set literal quote style
+## Set literal quote style
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -85,7 +84,7 @@ e: |-
   true
 ```
 
-### Set folded quote style
+## Set folded quote style
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -109,7 +108,7 @@ e: >-
   true
 ```
 
-### Set flow quote style
+## Set flow quote style
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -126,7 +125,9 @@ will output
 {a: cat, b: 5, c: 3.2, e: true}
 ```
 
-### Set empty (default) quote style
+## Pretty print
+Set empty (default) quote style
+
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -146,11 +147,10 @@ c: 3.2
 e: true
 ```
 
-### Read style
+## Read style
 Given a sample.yml file of:
 ```yaml
-a: cat
+{a: "cat", b: 'thing'}
-b: thing
 ```
 then
 ```bash
@@ -158,8 +158,8 @@ yq eval '.. | style' sample.yml
 ```
 will output
 ```yaml
-
+flow
-
+double
-
+single
 ```
 

pkg/yqlib/doc/Tag.md

@@ -1,6 +1,5 @@
-The tag operator can be used to get or set the tag of ndoes (e.g. `!!str`, `!!int`, `!!bool`).
+The tag operator can be used to get or set the tag of nodes (e.g. `!!str`, `!!int`, `!!bool`).
-## Examples
+## Get tag
-### Get tag
 Given a sample.yml file of:
 ```yaml
 a: cat
@@ -23,7 +22,7 @@ will output
 !!seq
 ```
 
-### Convert numbers to strings
+## Convert numbers to strings
 Given a sample.yml file of:
 ```yaml
 a: cat

pkg/yqlib/doc/Traverse.md

@@ -1,6 +1,5 @@
-This is the simples (and perhaps most used) operator, it is used to navigate deeply into yaml structurse.
+This is the simplest (and perhaps most used) operator, it is used to navigate deeply into yaml structurse.
-## Examples
+## Simple map navigation
-### Simple map navigation
 Given a sample.yml file of:
 ```yaml
 a:
@@ -15,7 +14,7 @@ will output
 b: apple
 ```
 
-### Splat
+## Splat
 Often used to pipe children into other operators
 
 Given a sample.yml file of:
@@ -33,7 +32,23 @@ b: apple
 c: banana
 ```
 
-### Children don't exist
+## Special characters
+Use quotes around path elements with special characters
+
+Given a sample.yml file of:
+```yaml
+"{}": frog
+```
+then
+```bash
+yq eval '."{}"' sample.yml
+```
+will output
+```yaml
+frog
+```
+
+## Children don't exist
 Nodes are added dynamically while traversing
 
 Given a sample.yml file of:
@@ -49,7 +64,7 @@ will output
 null
 ```
 
-### Wildcard matching
+## Wildcard matching
 Given a sample.yml file of:
 ```yaml
 a:
@@ -66,7 +81,7 @@ apple
 things
 ```
 
-### Aliases
+## Aliases
 Given a sample.yml file of:
 ```yaml
 a: &cat
@@ -82,7 +97,7 @@ will output
 *cat
 ```
 
-### Traversing aliases with splat
+## Traversing aliases with splat
 Given a sample.yml file of:
 ```yaml
 a: &cat
@@ -98,7 +113,7 @@ will output
 frog
 ```
 
-### Traversing aliases explicitly
+## Traversing aliases explicitly
 Given a sample.yml file of:
 ```yaml
 a: &cat
@@ -114,7 +129,7 @@ will output
 frog
 ```
 
-### Traversing arrays by index
+## Traversing arrays by index
 Given a sample.yml file of:
 ```yaml
 - 1
@@ -130,7 +145,7 @@ will output
 1
 ```
 
-### Maps with numeric keys
+## Maps with numeric keys
 Given a sample.yml file of:
 ```yaml
 2: cat
@@ -144,7 +159,7 @@ will output
 cat
 ```
 
-### Maps with non existing numeric keys
+## Maps with non existing numeric keys
 Given a sample.yml file of:
 ```yaml
 a: b
@@ -158,7 +173,7 @@ will output
 null
 ```
 
-### Traversing merge anchors
+## Traversing merge anchors
 Given a sample.yml file of:
 ```yaml
 foo: &foo
@@ -189,7 +204,7 @@ will output
 foo_a
 ```
 
-### Traversing merge anchors with override
+## Traversing merge anchors with override
 Given a sample.yml file of:
 ```yaml
 foo: &foo
@@ -220,7 +235,7 @@ will output
 foo_c
 ```
 
-### Traversing merge anchors with local override
+## Traversing merge anchors with local override
 Given a sample.yml file of:
 ```yaml
 foo: &foo
@@ -251,7 +266,7 @@ will output
 foobar_thing
 ```
 
-### Splatting merge anchors
+## Splatting merge anchors
 Given a sample.yml file of:
 ```yaml
 foo: &foo
@@ -284,7 +299,7 @@ foo_a
 foobar_thing
 ```
 
-### Traversing merge anchor lists
+## Traversing merge anchor lists
 Note that the later merge anchors override previous
 
 Given a sample.yml file of:
@@ -317,7 +332,7 @@ will output
 bar_thing
 ```
 
-### Splatting merge anchor lists
+## Splatting merge anchor lists
 Given a sample.yml file of:
 ```yaml
 foo: &foo

pkg/yqlib/doc/Union.md

@@ -1,6 +1,5 @@
 This operator is used to combine different results together.
-## Examples
+## Combine scalars
-### Combine scalars
 Running
 ```bash
 yq eval --null-input '1, true, "cat"'
@@ -12,7 +11,7 @@ true
 cat
 ```
 
-### Combine selected paths
+## Combine selected paths
 Given a sample.yml file of:
 ```yaml
 a: fieldA

pkg/yqlib/doc/headers/Boolean Operators.md

@@ -1 +1 @@
-The `or` and `and` operators take two parameters and return a boolean result. These are most commonly used with the `select` operator to filter particular nodes.
+The `or` and `and` operators take two parameters and return a boolean result. `not` flips a boolean from true to false, or vice versa. These are most commonly used with the `select` operator to filter particular nodes.

pkg/yqlib/doc/headers/Document Index.md

@@ -0,0 +1 @@
+Use the `documentIndex` operator to select nodes of a particular document.

pkg/yqlib/doc/headers/Equals.md

@@ -1,5 +1,3 @@
-## Equals Operator
-
 This is a boolean operator that will return ```true``` if the LHS is equal to the RHS and ``false`` otherwise.
 
 ```

pkg/yqlib/doc/headers/File Operators.md

@@ -1,5 +1,7 @@
 File operators are most often used with merge when needing to merge specific files together. Note that when doing this, you will need to use `eval-all` to ensure all yaml documents are loaded into memory before performing the merge (as opposed to `eval` which runs the expression once per document).
 
+## Merging files
+Note the use of eval-all to ensure all documents are loaded into memory.
 ```bash
 yq eval-all 'select(fileIndex == 0) * select(filename == "file2.yaml")' file1.yaml file2.yaml
 ```

pkg/yqlib/doc/headers/Multiply.md

@@ -3,3 +3,10 @@ Like the multiple operator in `jq`, depending on the operands, this multiply ope
 Upcoming versions of `yq` will add support for other types of multiplication (numbers, strings).
 
 Note that when merging objects, this operator returns the merged object (not the parent). This will be clearer in the examples below.
+
+## Merging files
+Note the use of eval-all to ensure all documents are loaded into memory.
+
+```bash
+yq eval-all 'select(fileIndex == 0) * select(fileIndex == 1)' file1.yaml file2.yaml
+```

pkg/yqlib/doc/headers/Not Operator.md

@@ -1 +0,0 @@
-This is a boolean operator and will return `true` when given a `false` value (including null), and `false` otherwise.

pkg/yqlib/doc/headers/Path Operator.md

@@ -1 +0,0 @@
-The path operator can be used to find the traversal paths of matching nodes in an expression. The path is returned as an array, which if traversed in order will lead to the matching node.

pkg/yqlib/doc/headers/Path.md

@@ -0,0 +1 @@
+The path operator can be used to get the traversal paths of matching nodes in an expression. The path is returned as an array, which if traversed in order will lead to the matching node.

pkg/yqlib/doc/headers/Tag Operator.md

@@ -1 +0,0 @@
-The tag operator can be used to get or set the tag of ndoes (e.g. `!!str`, `!!int`, `!!bool`).

pkg/yqlib/doc/headers/Tag.md

@@ -0,0 +1 @@
+The tag operator can be used to get or set the tag of nodes (e.g. `!!str`, `!!int`, `!!bool`).

pkg/yqlib/doc/headers/Traverse Operator.md

@@ -1 +0,0 @@
-This is the simples (and perhaps most used) operator, it is used to navigate deeply into yaml structurse.

pkg/yqlib/doc/headers/Traverse.md

@@ -0,0 +1 @@
+This is the simplest (and perhaps most used) operator, it is used to navigate deeply into yaml structurse.

pkg/yqlib/operator_assign_test.go

@@ -88,6 +88,7 @@ var assignOperatorScenarios = []expressionScenario{
 	},
 	{
 		description:           "Update empty object",
+		dontFormatInputForDoc: true,
 		document:              `{}`,
 		expression:            `.a.b |= "bogs"`,
 		expected: []string{
@@ -96,6 +97,7 @@ var assignOperatorScenarios = []expressionScenario{
 	},
 	{
 		description:           "Update empty object and array",
+		dontFormatInputForDoc: true,
 		document:              `{}`,
 		expression:            `.a.b[0] |= "bogs"`,
 		expected: []string{
@@ -116,5 +118,5 @@ func TestAssignOperatorScenarios(t *testing.T) {
 	for _, tt := range assignOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Assign Operator", assignOperatorScenarios)
+	documentScenarios(t, "Assign", assignOperatorScenarios)
 }

pkg/yqlib/operator_booleans.go

@@ -94,3 +94,20 @@ func AndOperator(d *dataTreeNavigator, matchingNodes *list.List, pathNode *PathT
 		return b1 && b2
 	})
 }
+
+func NotOperator(d *dataTreeNavigator, matchMap *list.List, pathNode *PathTreeNode) (*list.List, error) {
+	log.Debugf("-- notOperation")
+	var results = list.New()
+
+	for el := matchMap.Front(); el != nil; el = el.Next() {
+		candidate := el.Value.(*CandidateNode)
+		log.Debug("notOperation checking %v", candidate)
+		truthy, errDecoding := isTruthy(candidate)
+		if errDecoding != nil {
+			return nil, errDecoding
+		}
+		result := createBooleanCandidate(candidate, !truthy)
+		results.PushBack(result)
+	}
+	return results, nil
+}

pkg/yqlib/operator_booleans_test.go

@@ -45,6 +45,56 @@ var booleanOperatorScenarios = []expressionScenario{
 			"D0, P[b], (!!bool)::true\n",
 		},
 	},
+	{
+		description: "Not true is false",
+		expression:  `true | not`,
+		expected: []string{
+			"D0, P[], (!!bool)::false\n",
+		},
+	},
+	{
+		description: "Not false is true",
+		expression:  `false | not`,
+		expected: []string{
+			"D0, P[], (!!bool)::true\n",
+		},
+	},
+	{
+		description: "String values considered to be true",
+		expression:  `"cat" | not`,
+		expected: []string{
+			"D0, P[], (!!bool)::false\n",
+		},
+	},
+	{
+		description: "Empty string value considered to be true",
+		expression:  `"" | not`,
+		expected: []string{
+			"D0, P[], (!!bool)::false\n",
+		},
+	},
+	{
+		description: "Numbers are considered to be true",
+		expression:  `1 | not`,
+		expected: []string{
+			"D0, P[], (!!bool)::false\n",
+		},
+	},
+	{
+		description: "Zero is considered to be true",
+		expression:  `0 | not`,
+		expected: []string{
+			"D0, P[], (!!bool)::false\n",
+		},
+	},
+	{
+
+		description: "Null is considered to be false",
+		expression:  `~ | not`,
+		expected: []string{
+			"D0, P[], (!!bool)::true\n",
+		},
+	},
 }
 
 func TestBooleanOperatorScenarios(t *testing.T) {

pkg/yqlib/operator_collect_object.go

@@ -2,6 +2,8 @@ package yqlib
 
 import (
 	"container/list"
+
+	yaml "gopkg.in/yaml.v3"
 )
 
 /*
@@ -19,7 +21,9 @@ func CollectObjectOperator(d *dataTreeNavigator, matchMap *list.List, pathNode *
 	log.Debugf("-- collectObjectOperation")
 
 	if matchMap.Len() == 0 {
-		return list.New(), nil
+		node := &yaml.Node{Kind: yaml.MappingNode, Tag: "!!map", Value: "{}"}
+		candidate := &CandidateNode{Node: node}
+		return nodeToMap(candidate), nil
 	}
 	first := matchMap.Front().Value.(*CandidateNode)
 	var rotated []*list.List = make([]*list.List, len(first.Node.Content))

pkg/yqlib/operator_collect_object_test.go

@@ -9,7 +9,9 @@ var collectObjectOperatorScenarios = []expressionScenario{
 		description: `Collect empty object`,
 		document:    ``,
 		expression:  `{}`,
-		expected:    []string{},
+		expected: []string{
+			"D0, P[], (!!map)::{}\n",
+		},
 	},
 	{
 		description: `Wrap (prefix) existing object`,

pkg/yqlib/operator_comments_test.go

@@ -75,5 +75,5 @@ func TestCommentOperatorScenarios(t *testing.T) {
 	for _, tt := range commentOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Comments Operator", commentOperatorScenarios)
+	documentScenarios(t, "Comment Operators", commentOperatorScenarios)
 }

pkg/yqlib/operator_delete_test.go

@@ -43,5 +43,5 @@ func TestDeleteOperatorScenarios(t *testing.T) {
 	for _, tt := range deleteOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Delete Operator", deleteOperatorScenarios)
+	documentScenarios(t, "Delete", deleteOperatorScenarios)
 }

pkg/yqlib/operator_document_index_test.go

@@ -37,5 +37,5 @@ func TestDocumentIndexScenarios(t *testing.T) {
 	for _, tt := range documentIndexScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Document Index Operator", documentIndexScenarios)
+	documentScenarios(t, "Document Index", documentIndexScenarios)
 }

pkg/yqlib/operator_equals_test.go

@@ -54,5 +54,5 @@ func TestEqualOperatorScenarios(t *testing.T) {
 	for _, tt := range equalsOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Equals Operator", equalsOperatorScenarios)
+	documentScenarios(t, "Equals", equalsOperatorScenarios)
 }

pkg/yqlib/operator_explode_test.go

@@ -86,5 +86,5 @@ func TestExplodeOperatorScenarios(t *testing.T) {
 	for _, tt := range explodeTest {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Explode Operator", explodeTest)
+	documentScenarios(t, "Explode", explodeTest)
 }

pkg/yqlib/operator_multiply_test.go

@@ -130,5 +130,5 @@ func TestMultiplyOperatorScenarios(t *testing.T) {
 	for _, tt := range multiplyOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Multiply Operator", multiplyOperatorScenarios)
+	documentScenarios(t, "Multiply", multiplyOperatorScenarios)
 }

pkg/yqlib/operator_not.go

@@ -1,20 +0,0 @@
-package yqlib
-
-import "container/list"
-
-func NotOperator(d *dataTreeNavigator, matchMap *list.List, pathNode *PathTreeNode) (*list.List, error) {
-	log.Debugf("-- notOperation")
-	var results = list.New()
-
-	for el := matchMap.Front(); el != nil; el = el.Next() {
-		candidate := el.Value.(*CandidateNode)
-		log.Debug("notOperation checking %v", candidate)
-		truthy, errDecoding := isTruthy(candidate)
-		if errDecoding != nil {
-			return nil, errDecoding
-		}
-		result := createBooleanCandidate(candidate, !truthy)
-		results.PushBack(result)
-	}
-	return results, nil
-}

pkg/yqlib/operator_not_test.go

@@ -1,65 +0,0 @@
-package yqlib
-
-import (
-	"testing"
-)
-
-var notOperatorScenarios = []expressionScenario{
-	{
-		description: "Not true is false",
-		expression:  `true | not`,
-		expected: []string{
-			"D0, P[], (!!bool)::false\n",
-		},
-	},
-	{
-		description: "Not false is true",
-		expression:  `false | not`,
-		expected: []string{
-			"D0, P[], (!!bool)::true\n",
-		},
-	},
-	{
-		description: "String values considered to be true",
-		expression:  `"cat" | not`,
-		expected: []string{
-			"D0, P[], (!!bool)::false\n",
-		},
-	},
-	{
-		description: "Empty string value considered to be true",
-		expression:  `"" | not`,
-		expected: []string{
-			"D0, P[], (!!bool)::false\n",
-		},
-	},
-	{
-		description: "Numbers are considered to be true",
-		expression:  `1 | not`,
-		expected: []string{
-			"D0, P[], (!!bool)::false\n",
-		},
-	},
-	{
-		description: "Zero is considered to be true",
-		expression:  `0 | not`,
-		expected: []string{
-			"D0, P[], (!!bool)::false\n",
-		},
-	},
-	{
-
-		description: "Null is considered to be false",
-		expression:  `~ | not`,
-		expected: []string{
-			"D0, P[], (!!bool)::true\n",
-		},
-	},
-}
-
-func TestNotOperatorScenarios(t *testing.T) {
-	for _, tt := range notOperatorScenarios {
-		testScenario(t, &tt)
-	}
-	documentScenarios(t, "Not Operator", notOperatorScenarios)
-}

pkg/yqlib/operator_path_test.go

@@ -41,5 +41,5 @@ func TestPathOperatorsScenarios(t *testing.T) {
 	for _, tt := range pathOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Path Operator", pathOperatorScenarios)
+	documentScenarios(t, "Path", pathOperatorScenarios)
 }

pkg/yqlib/operator_recursive_descent_test.go

@@ -23,7 +23,7 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		},
 	},
 	{
-		description: "Map",
+		skipDoc:    true,
 		document:   `{a: {b: apple}}`,
 		expression: `..`,
 		expected: []string{
@@ -33,7 +33,7 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		},
 	},
 	{
-		description: "Array",
+		skipDoc:    true,
 		document:   `[1,2,3]`,
 		expression: `..`,
 		expected: []string{
@@ -44,7 +44,7 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		},
 	},
 	{
-		description: "Array of maps",
+		skipDoc:    true,
 		document:   `[{a: cat},2,true]`,
 		expression: `..`,
 		expected: []string{
@@ -58,23 +58,17 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 	{
 		description: "Aliases are not traversed",
 		document:    `{a: &cat {c: frog}, b: *cat}`,
-		expression:  `..`,
+		expression:  `[..]`,
 		expected: []string{
-			"D0, P[], (!!map)::{a: &cat {c: frog}, b: *cat}\n",
+			"D0, P[a], (!!seq)::- {a: &cat {c: frog}, b: *cat}\n- &cat {c: frog}\n- frog\n- *cat\n",
-			"D0, P[a], (!!map)::&cat {c: frog}\n",
-			"D0, P[a c], (!!str)::frog\n",
-			"D0, P[b], (alias)::*cat\n",
 		},
 	},
 	{
 		description: "Merge docs are not traversed",
 		document:    mergeDocSample,
-		expression:  `.foobar | ..`,
+		expression:  `.foobar | [..]`,
 		expected: []string{
-			"D0, P[foobar], (!!map)::c: foobar_c\n!!merge <<: *foo\nthing: foobar_thing\n",
+			"D0, P[foobar], (!!seq)::- c: foobar_c\n  !!merge <<: *foo\n  thing: foobar_thing\n- foobar_c\n- *foo\n- foobar_thing\n",
-			"D0, P[foobar c], (!!str)::foobar_c\n",
-			"D0, P[foobar <<], (alias)::*foo\n",
-			"D0, P[foobar thing], (!!str)::foobar_thing\n",
 		},
 	},
 	{
@@ -96,5 +90,5 @@ func TestRecursiveDescentOperatorScenarios(t *testing.T) {
 	for _, tt := range recursiveDescentOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Recursive Descent Operator", recursiveDescentOperatorScenarios)
+	documentScenarios(t, "Recursive Descent", recursiveDescentOperatorScenarios)
 }

pkg/yqlib/operator_select_test.go

@@ -59,5 +59,5 @@ func TestSelectOperatorScenarios(t *testing.T) {
 	for _, tt := range selectOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Select Operator", selectOperatorScenarios)
+	documentScenarios(t, "Select", selectOperatorScenarios)
 }

pkg/yqlib/operator_style_test.go

@@ -70,7 +70,8 @@ e: >-
 		},
 	},
 	{
-		description: "Set empty (default) quote style",
+		description:    "Pretty print",
+		subdescription: "Set empty (default) quote style",
 		document:       `{a: cat, b: 5, c: 3.2, e: true}`,
 		expression:     `.. style=""`,
 		expected: []string{
@@ -88,6 +89,7 @@ e: >-
 	{
 		description:           "Read style",
 		document:              `{a: "cat", b: 'thing'}`,
+		dontFormatInputForDoc: true,
 		expression:            `.. | style`,
 		expected: []string{
 			"D0, P[], (!!str)::flow\n",
@@ -110,5 +112,5 @@ func TestStyleOperatorScenarios(t *testing.T) {
 	for _, tt := range styleOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Style Operator", styleOperatorScenarios)
+	documentScenarios(t, "Style", styleOperatorScenarios)
 }

pkg/yqlib/operator_tag_test.go

@@ -32,5 +32,5 @@ func TestTagOperatorScenarios(t *testing.T) {
 	for _, tt := range tagOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Tag Operator", tagOperatorScenarios)
+	documentScenarios(t, "Tag", tagOperatorScenarios)
 }

pkg/yqlib/operator_traverse_path_test.go

@@ -45,6 +45,15 @@ var traversePathOperatorScenarios = []expressionScenario{
 			"D0, P[1], (!!map)::{c: banana}\n",
 		},
 	},
+	{
+		description:    "Special characters",
+		subdescription: "Use quotes around path elements with special characters",
+		document:       `{"{}": frog}`,
+		expression:     `."{}"`,
+		expected: []string{
+			"D0, P[{}], (!!str)::frog\n",
+		},
+	},
 	{
 		description:    "Children don't exist",
 		subdescription: "Nodes are added dynamically while traversing",
@@ -271,5 +280,5 @@ func TestTraversePathOperatorScenarios(t *testing.T) {
 	for _, tt := range traversePathOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Traverse Operator", traversePathOperatorScenarios)
+	documentScenarios(t, "Traverse", traversePathOperatorScenarios)
 }

pkg/yqlib/operator_union_test.go

@@ -29,5 +29,5 @@ func TestUnionOperatorScenarios(t *testing.T) {
 	for _, tt := range unionOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Union Operator", unionOperatorScenarios)
+	documentScenarios(t, "Union", unionOperatorScenarios)
 }

pkg/yqlib/operators_test.go

@@ -114,17 +114,13 @@ func documentScenarios(t *testing.T, title string, scenarios []expressionScenari
 	}
 
 	w := bufio.NewWriter(f)
+	writeOrPanic(w, "\n")
 
-	writeOrPanic(w, "\n## Examples\n")
+	for _, s := range scenarios {
-
-	for index, s := range scenarios {
 		if !s.skipDoc {
 
-			if s.description != "" {
+			writeOrPanic(w, fmt.Sprintf("## %v\n", s.description))
-				writeOrPanic(w, fmt.Sprintf("### %v\n", s.description))
+
-			} else {
-				writeOrPanic(w, fmt.Sprintf("### Example %v\n", index))
-			}
 			if s.subdescription != "" {
 				writeOrPanic(w, s.subdescription)
 				writeOrPanic(w, "\n\n")
@@ -132,7 +128,7 @@ func documentScenarios(t *testing.T, title string, scenarios []expressionScenari
 			formattedDoc := ""
 			if s.document != "" {
 				if s.dontFormatInputForDoc {
-					formattedDoc = s.document
+					formattedDoc = s.document + "\n"
 				} else {
 					formattedDoc = formatYaml(s.document)
 				}