Base.Error
SourceA lazy string, implemented with Info
, but intended specifically for error messages.
to_string_hum
forces the lazy message, which might be an expensive operation.
to_string_hum
usually produces a sexp; however, it is guaranteed that to_string_hum (of_string s) = s
.
If this string is going to go into a log file, you may find it useful to ensure that the string is only one line long. To do this, use to_string_mach t
.
Be careful that the body of the lazy or thunk does not access mutable data, since it will only be called at an undetermined later point.
For create message a sexp_of_a
, sexp_of_a a
is lazily computed, when the info is converted to a sexp. So if a
is mutated in the time between the call to create
and the sexp conversion, those mutations will be reflected in the sexp. Use ~strict:()
to force sexp_of_a a
to be computed immediately.
Constructs a t
containing only a string from a format. This eagerly constructs the string.
Adds a string and some other data in the form of an s-expression at the front.
of_exn
and to_exn
are primarily used with Error
, but their definitions have to be here because they refer to the underlying representation.
~backtrace:`Get
attaches the backtrace for the most recent exception. The same caveats as for Printexc.print_backtrace
apply. ~backtrace:(`This s)
attaches the backtrace s
. The default is no backtrace.
Note that the exception raised by this function maintains a reference to the t
passed in.