Flesh out commands a bit more

README.md

@@ -1,6 +1,39 @@
 # today
 
-## `DATE` annotations
+## Commands
+
+### The `TASK` command
+
+```
+TASK title
+(DATE annotation)*
+[FROM annotation]
+[UNTIL annotation]
+(DONE annotation)*
+    long description
+```
+
+### The `NOTE` command
+
+```
+NOTE title
+(DATE annotation)+
+[FROM annotation]
+[UNTIL annotation]
+(DONE annotation)*
+    long description
+```
+
+### The `BIRTHDAY` command
+
+```
+BIRTHDAY name
+BDATE annotation
+```
+
+## Annotations
+
+### The `DATE` annotation
 
 Most commands allow or require `DATE` annotations. They are roughly structured
 like `DATE start [-- end]`. The `end` part can only contain time-related
@@ -26,6 +59,27 @@ a semicolon.
 If multiple `DATE` annotations from a single command start on the same date, all
 except the first are ignored.
 
+### The `FROM` and `UNTIL` annotations
+
+Commands that allow `DATE` annotations also allow the `FROM` and `UNTIL`
+annotations. These can be used to restrict occurrences of entries.
+
+The `FROM` annotation has the form `FROM date` and only keeps occurences that
+end at or after the specified date. These occurences may begin before the
+specified date.
+
+The `UNTIL` annotation has the form `UNTIL date` and only keeps occurrences that
+start at or before the specified date. These occurrences may extend past the
+specified date.
+
+### The `BDATE` annotations
+
+This is a very simple date annotation for birthdays. It has the form
+`BDATE date` where the year may optionally be replaced by a `?`.
+
+If the year is specified, the person's current age is displayed in the birthday
+occurrence title.
+
 ## Examples
 ```
 NOTE Spielerunde
@@ -52,4 +106,10 @@ DATE (wd = sat) -- +d
 
 NOTE last of each month
 DATE (m = 1) -d
+
+BIRTHDAY Max
+BDATE 1987-05-14
+
+BIRTHDAY Martha
+BDATE ?-09-21
 ```