Added global xml prefs for simplicity

pkg/yqlib/doc/operators/encode-decode.md

@@ -14,11 +14,13 @@ These operators are useful to process yaml documents that have stringified embed
 | Properties |  | to_props/@props |
 | CSV |  | to_csv/@csv |
 | TSV |  | to_tsv/@tsv |
-| XML | from_xml |  |
+| XML | from_xml | to_xml(i)/@xml |
 
 
 CSV and TSV format both accept either a single array or scalars (representing a single row), or an array of array of scalars (representing multiple rows). 
 
+XML uses the `--xml-attribute-prefix` and `xml-content-name` flags to identify attributes and content fields.
+
 
 ## Encode value as json string
 Given a sample.yml file of:
@@ -272,6 +274,61 @@ cat	thing1,thing2	true	3.40
 dog	thing3	false	12
 ```
 
+## Encode value as xml string
+Given a sample.yml file of:
+```yaml
+a:
+  cool:
+    foo: bar
+    +id: hi
+```
+then
+```bash
+yq eval '.a | to_xml' sample.yml
+```
+will output
+```yaml
+<cool id="hi">
+  <foo>bar</foo>
+</cool>
+```
+
+## Encode value as xml string on a single line
+Given a sample.yml file of:
+```yaml
+a:
+  cool:
+    foo: bar
+    +id: hi
+```
+then
+```bash
+yq eval '.a | @xml' sample.yml
+```
+will output
+```yaml
+<cool id="hi"><foo>bar</foo></cool>
+```
+
+## Encode value as xml string with custom indentation
+Given a sample.yml file of:
+```yaml
+a:
+  cool:
+    foo: bar
+    +id: hi
+```
+then
+```bash
+yq eval '.a | to_xml(1)' sample.yml
+```
+will output
+```yaml
+<cool id="hi">
+ <foo>bar</foo>
+</cool>
+```
+
 ## Decode a xml encoded string
 Given a sample.yml file of:
 ```yaml

pkg/yqlib/doc/operators/headers/encode-decode.md

@@ -14,8 +14,10 @@ These operators are useful to process yaml documents that have stringified embed
 | Properties |  | to_props/@props |
 | CSV |  | to_csv/@csv |
 | TSV |  | to_tsv/@tsv |
-| XML | from_xml |  |
+| XML | from_xml | to_xml(i)/@xml |
 
 
 CSV and TSV format both accept either a single array or scalars (representing a single row), or an array of array of scalars (representing multiple rows). 
 
+XML uses the `--xml-attribute-prefix` and `xml-content-name` flags to identify attributes and content fields.
+

pkg/yqlib/doc/usage/headers/xml.md

@@ -1,8 +1,10 @@
 # XML
 
-At the moment, `yq` only supports decoding `xml` (into one of the other supported output formats).
+Encode and decode to and from XML. Whitespace is not conserved for round trips - but the order of the fields are.
 
-As yaml does not have the concept of attributes, these are converted to regular fields with a prefix to prevent clobbering. Consecutive xml nodes with the same name are assumed to be arrays.
+As yaml does not have the concept of attributes, xml attributes are converted to regular fields with a prefix to prevent clobbering. This defaults to "+", use the `--xml-attribute-prefix` to change.
+
+Consecutive xml nodes with the same name are assumed to be arrays.
 
 All values in XML are assumed to be strings - but you can use `from_yaml` to parse them into their correct types:
 
@@ -10,3 +12,12 @@ All values in XML are assumed to be strings - but you can use `from_yaml` to par
 ```
 yq e -p=xml '.myNumberField |= from_yaml' my.xml
 ```
+
+
+XML nodes that have attributes then plain content, e.g:
+
+```xml
+<cat name="tiger">meow</cat>
+```
+
+The content of the node will be set as a field in the map with the key "+content". Use the `--xml-content-name` flag to change this.

pkg/yqlib/doc/usage/xml.md

@@ -1,8 +1,10 @@
 # XML
 
-At the moment, `yq` only supports decoding `xml` (into one of the other supported output formats).
+Encode and decode to and from XML. Whitespace is not conserved for round trips - but the order of the fields are.
 
-As yaml does not have the concept of attributes, these are converted to regular fields with a prefix to prevent clobbering. Consecutive xml nodes with the same name are assumed to be arrays.
+As yaml does not have the concept of attributes, xml attributes are converted to regular fields with a prefix to prevent clobbering. This defaults to "+", use the `--xml-attribute-prefix` to change.
+
+Consecutive xml nodes with the same name are assumed to be arrays.
 
 All values in XML are assumed to be strings - but you can use `from_yaml` to parse them into their correct types:
 
@@ -11,6 +13,15 @@ All values in XML are assumed to be strings - but you can use `from_yaml` to par
 yq e -p=xml '.myNumberField |= from_yaml' my.xml
 ```
 
+
+XML nodes that have attributes then plain content, e.g:
+
+```xml
+<cat name="tiger">meow</cat>
+```
+
+The content of the node will be set as a field in the map with the key "+content". Use the `--xml-content-name` flag to change this.
+
 ## Parse xml: simple
 Given a sample.xml file of:
 ```xml
@@ -97,8 +108,7 @@ yq e -o=xml '.' sample.yml
 ```
 will output
 ```xml
-<cat>purrs</cat>
-```
+<cat>purrs</cat>```
 
 ## Encode xml: array
 Given a sample.yml file of:
@@ -117,8 +127,7 @@ will output
 <pets>
   <cat>purrs</cat>
   <cat>meows</cat>
-</pets>
-```
+</pets>```
 
 ## Encode xml: attributes
 Fields with the matching xml-attribute-prefix are assumed to be attributes.
@@ -138,8 +147,7 @@ will output
 ```xml
 <cat name="tiger">
   <meows>true</meows>
-</cat>
-```
+</cat>```
 
 ## Encode xml: attributes with content
 Fields with the matching xml-content-name is assumed to be content.
@@ -157,6 +165,5 @@ yq e -o=xml '.' sample.yml
 ```
 will output
 ```xml
-<cat name="tiger">cool</cat>
-```
+<cat name="tiger">cool</cat>```