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pkg/yqlib/doc/usage/properties.md

@@ -4,6 +4,12 @@ Encode to a property file (decode not yet supported). Line comments on value nod
 
 By default, empty maps and arrays are not encoded - see below for an example on how to encode a value for these.
 
+{% hint style="warning" %}
+Note that versions prior to 4.18 require the 'eval/e' command to be specified. 
+
+`yq e <exp> <file>`
+{% endhint %}
+
 ## Encode properties
 Note that empty arrays and maps are not encoded by default.