I am working on a project were I have to read line form ( PLC ) programmable logic controller generated text file with lines like this
Circuit Value Current 2.33 4.32 5.55
there could be up to 3000 lines per txt file
I am using string stream to parse the line , for the sake of good programming I which to check weather first three values are string and last three values are actually floats
raise or throw an exception if they are not , any help in this regard would be much appreciated .
it is not pattern matching , more data validation , thank you for your post , I actually did this with boost::lexical_cast , throws an exception if the required value is neither float or a string.
depends on how you set it up.
Often input data validation involves some kind of pattern matching, so OReubens' suggestion is still relevant, though it may or may not be ideal for your case.
Originally Posted by aamir121a
I actually did this with boost::lexical_cast , throws an exception if the required value is neither float or a string.
Internally, boost::lexical_cast uses stringstreams. The basic idea here is to just parse with the stringstream, then check the state of the stringstream. If it is in a good state, or if you have reached the end and it is in EOF but not fail state, then the input can be considered valid.