Embedded Systems LM5p-GSM, Руководство по эксплуатации продукта

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1. testfn = function ( t )
2. return t * t
3. end
4. result = storage.set ( 'my_stored_value_2' , testfn ) -- this will result in an error

The following examples shows the basic syntax of storage.get . Assuming that key value
was not found, first call will return nil while second call will return number 0 which was
specified as a default value.
1. result = storage.get ( 'my_stored_value_3' ) -- returns nil if value is not found
2. result = storage.get ( 'my_stored_value_3' , 0 ) -- returns 0 if value is not found

When storing tables make sure to check the returned result type. Assume we have
created a storage item with key
test_object_data .
1. objectdata ={}
2. objectdata.temperature = 23.1
3. objectdata.scene = 'default'
4. result = storage.set ( 'test_object_data' , objectdata ) -- store objectdata variable as
'test_object_data'

Now we are retrieving data from storage. Data type is checked for correctness.
1. objectdata = storage.get ( 'test_object_data' )
2. if type ( objectdata )== 'table' then
3. if objectdata.temperature > 24 then
4. -- do something if temperature level is too high
5. end
6. end
6.2.14. Alert function
alert(message, [var1, [var2, [var3]]])
Stores alert message and current system time in the main database. All alerts are accessible in
the "Alerts" module. This function behaves exactly as Lua
string.format .
Example
1. temperature = 25.3
2. if temperature > 24 then
3. -- resulting message: 'Temperature levels are too high: 25.3'
4. alert ( 'Temperature level is too high: %.1f' , temperature )
5. end