validity test for Float

[Craig]

Q from a newbie:

Is there any way to test if a string is valid to pass to Float?

irb(main):025:0> Float( "2.0" )
=> 2.0
irb(main):026:0> Float( "mambo" )
ArgumentError: invalid value for Float(): "mambo"
from (irb):26:in `Float'
from (irb):26
irb(main):027:0> "2.0".to_f
=> 2.0
irb(main):028:0> "mambo".to_f
=> 0.0

to_f doesn't seem to do it, as it returns 0.0 even if the string is
invalid.

Many TIA,
Craig

 

[Sammyo]

You could consider converting to a appropriate base:
=> 273481.0

(not sure why a lower base didn't work)

Oh, and for the too literal ->

 

[Craig]

Thanks super! It works, but feels somewhat kludgy. It would be nice
to have some sort of String#isnum? as a built-in.
Craig