1 files changed, 103 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/Lang/README.md b/www/wiki/extensions/SemanticMediaWiki/src/Lang/README.md
new file mode 100644
index 00000000..2a2c3cd4
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/Lang/README.md
@@ -0,0 +1,103 @@
+It provides "extraneous" language functions independent of MediaWiki that ate required by Semantic MediaWiki and its registration system.
+
+## JSON format
+
+The location of the content files is determined by the [`$smwgExtraneousLanguageFileDir`](https://www.semantic-mediawiki.org/wiki/Help:$smwgExtraneousLanguageFileDir) setting.
+
+### Field definitions
+
+- `fallback_language`defines a fallback language tag
+- `datatype`
+  - `labels` datatype labels
+  - `aliases` datatype aliases
+- `property`
+  - `labels` predefined property labels
+  - `aliases` predefined property aliases
+- `namespace`
+  - `labels` namespace names
+  - `aliases` namespace aliases
+- `date`
+  - `format` to a define a rule set of how to resolve preferred date formats for dates with 1, 2, and 3 components. It is defined as an array where the constants define the order of the interpretation.
+    - `SMW_MDY` Month-Day-Year
+    - `SMW_DMY` Day-Month-Year
+    - `SMW_YMD` Year-Month-Day
+    - `SMW_YDM` Year-Day-Month
+    - `SMW_MY` Month-Year
+    - `SMW_YM` Year-Month
+    - `SMW_Y` Year
+    - `SMW_YEAR` an entered digit can be a year
+    - `SMW_DAY` an entered digit can be a day
+    - `SMW_MONTH` an entered digit can be a month
+    - `SMW_DAY_MONTH_YEAR` an entered digit can be a day, month or year
+    - `SMW_DAY_YEAR` an entered digit can be either a day or a year
+  - `precision` used to define the rules of formatting for a specific precision:
+    - `SMW_PREC_Y` Year
+    - `SMW_PREC_YMD` Year, Month, and Day
+    - `SMW_PREC_YMDT` Year, Month, Day, and Time
+    - `SMW_PREC_YMDTZ` Year, Month, Day, Time and Timezone
+  - `months` twelve strings naming the months and short strings briefly naming the month
+  - `days` follows ISO-8601 numeric representation, starting with Monday together with the corresponding short name
+- `@...` fields leading with `@` are identified as comment fields
+
+### Example
+
+<pre>
+{
+	"fallback_language": false,
+	"datatype": {
+		"labels":{
+			"_wpg": "Page"
+		},
+		"aliases":{
+			"Page": "_wpg"
+		}
+	},
+	"property": {
+		"labels":{
+			"_TYPE": "Has type"
+		},
+		"aliases": {
+			"Has type": "_TYPE"
+		}
+	},
+	"namespaces": {
+		"labels":{
+			"SMW_NS_PROPERTY": "Property"
+		},
+		"aliases": {
+			"Property": "SMW_NS_PROPERTY"
+		}
+	},
+	"date":{
+		"precision": {
+			"SMW_PREC_YMDTZ": "H:i:s T, j F Y"
+		},
+		"format": [
+			[
+				"SMW_Y"
+			]
+		],
+		"months": [
+			[
+				"January",
+				"Jan"
+			]
+		]
+		"days":[
+			[
+				"Monday",
+				"Mon"
+			]
+		]
+	}
+}
+</pre>
+
+## Technical notes
+
+<pre>
+SMW\Lang
+├─ Lang 			# interface to the language functions
+├─ JsonContentsFileReader	# access the contents of a `JSON` file
+└─ FallbackFinder		# resolving a fallback language
+</pre>