b.successors.add(db)
db.predecessors.add(b)
else
- manager.notes.add(new Error(line.location,
+ manager.notes.add(new P8Error(line.location,
"this instruction is not followed by valid code as it should (misplaced data or missing BR?)"))
end
end
has_function_calls = true
var next_addr = line.address+4
if not addr_to_blocks.has_key(next_addr) then
- manager.notes.add(new Error(line.location,
+ manager.notes.add(new P8Error(line.location,
"this CALL is not followed by valide code as it should"))
else
b.after_call = addr_to_blocks[next_addr]
else if instr isa ARetInstruction then
if to_link.is_empty then
- manager.notes.add( new Error(instr.location,"no CALL can be linked to this RET") )
+ manager.notes.add( new P8Error(instr.location,"no CALL can be linked to this RET") )
return false
else
var caller = to_link.pop
if i == len-1 or line.address + line.size != lines[i+1].address then
if error then
if first == line then
- manager.notes.add(new Error(first.location, msg))
+ manager.notes.add(new P8Error(first.location, msg))
else
- manager.notes.add(new Error.range(first.location, line.location, msg))
+ manager.notes.add(new P8Error.range(first.location, line.location, msg))
end
else
if first == line then
- manager.notes.add(new Error(first.location, msg))
+ manager.notes.add(new P8Error(first.location, msg))
else
manager.notes.add(new Warn.range(first.location, line.location, msg))
end
--- /dev/null
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# This file is free software, which comes along with NIT. This software is
+# distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+# without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+# PARTICULAR PURPOSE. You can modify it is you want, provided this header
+# is kept unaltered, and a notification of the changes is added.
+# You are allowed to redistribute it and sell it, alone or is a part of
+# another product.
+
+# Standard error-management infrastructure.
+#
+module error
+
+import string
+
+# Standard class for error messages
+class Error
+ # A short human-readable error message.
+ #
+ # This message is short and informative and could be displayed on the console, a dialog-box
+ # or written in a log file.
+ #
+ # Message should be explicative, autonomous and do not depend on contextual information.
+ #
+ # Eg. instead of "Fatal error: cannot open file",
+ # something like "File error, cannot open /some/path/document.ext, file not found." is preferred,
+ # where the message is informative as it, and the severity of the error is not assumed:
+ # while fatal for the library, it could be something benign for the program.
+ var message: String
+
+ # An original error that caused the creation of this error, if any.
+ #
+ # This is used to chain errors and track the implication of various sub-systems for a given error.
+ #
+ # When displaying an error the end user, causes can be recursively displayed.
+ var cause: nullable Error = null is writable
+
+ redef fun to_s do return message
+end
+
+# Helper class used as a return value of methods that may give errors instead of values.
+#
+# Functions that return useful values or errors could use it to simulate an easy-to use multiple-return.
+#
+# ~~~
+# fun division(a,b: Int): MaybeError[Int, Error]
+# do
+# if b == 0 then return new MaybeError[Int, Error](null, new Error("Arithmetic Error: try to divide {a} by 0"))
+# return new MaybeError[Int, Error](a / b, null)
+# end
+#
+# assert division(10, 2).is_error == false
+# assert division(10, 0).is_error == true
+# ~~~
+#
+# Clients has to handle the error:
+#
+# ~~~
+# var res = division(10, 2)
+# if res.is_error then
+# print res.error
+# exit 1
+# end
+# print res.value
+# assert res.value == 5
+# ~~~
+class MaybeError[V, E: Error]
+ # The value, if any
+ var maybe_value: nullable V
+
+ # The error, if any
+ var maybe_error: nullable E
+
+ # It there an error?
+ fun is_error: Bool do return maybe_error != null
+
+ # The value
+ # REQUIRE: `not is_error`
+ fun value: V do return maybe_value.as(V)
+
+ # The require
+ # REQUIRE: `is_error`
+ fun error: E do return maybe_error.as(E)
+
+ redef fun to_s do
+ var e = maybe_error
+ if e != null then return e.to_s
+ return value.to_s
+ end
+end
nitlanguage / nit.git / commitdiff