How to Completely Disable Calls to Assert()

How can I completely disable calls to assert()?

You must #define NDEBUG (or use the flag -DNDEBUG with g++) this will disable assert as long as it's defined before the inclusion of the assert header file.

Does the NS_BLOCK_ASSERTIONS disable both NSAssert and assert() calls?

No, assert() is controlled with the NDEBUG symbol:

#ifdef NDEBUG
#define assert(e)   ((void)0)
#else
...

(see /usr/include/assert.h if you have the Xcode Command Line Tools installed, or elsewhere in the Xcode.app bundle, if not).

C++ suppress assertions in debug build

If you are talking about standard assert macro, you can turn it off by defining NDEBUG macro.

If NDEBUG is defined as a macro name at the point in the source code
where <cassert> is included, then assert does nothing.

Disable assertions in Python

#How do I disable assertions in Python?

There are multiple approaches that affect a single process, the environment, or a single line of code.

I demonstrate each.

For the whole process

Using the -O flag (capital O) disables all assert statements in a process.

For example:

$ python -Oc "assert False"

$ python -c "assert False"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
AssertionError

Note that by disable I mean it also does not execute the expression that follows it:

$ python -Oc "assert 1/0"

$ python -c "assert 1/0"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ZeroDivisionError: integer division or modulo by zero

For the environment

You can use an environment variable to set this flag as well.

This will affect every process that uses or inherits the environment.

E.g., in Windows, setting and then clearing the environment variable:

C:\>python -c "assert False"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
AssertionError
C:\>SET PYTHONOPTIMIZE=TRUE

C:\>python -c "assert False"

C:\>SET PYTHONOPTIMIZE=

C:\>python -c "assert False"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
AssertionError

Same in Unix (using set and unset for respective functionality)

Single point in code

You continue your question:

if an assertion fails, I don't want it to throw an AssertionError, but to keep going.

You can either ensure control flow does not reach the assertion, for example:

if False:
    assert False, "we know this fails, but we don't get here"

or if you want the assert expression to be exercised then you can catch the assertion error:

try:
    assert False, "this code runs, fails, and the exception is caught"
except AssertionError as e:
    print(repr(e))

which prints:

AssertionError('this code runs, fails, and the exception is caught')

and you'll keep going from the point you handled the AssertionError.

References

From the assert documentation:

An assert statement like this:

assert expression #, optional_message

Is equivalent to

if __debug__:
    if not expression: raise AssertionError #(optional_message)

And,

the built-in variable __debug__ is True under normal circumstances, False when optimization is requested (command line option -O).

and further

Assignments to __debug__ are illegal. The value for the built-in variable is determined when the interpreter starts.

From the usage docs:

-O

Turn on basic optimizations. This changes the filename extension for compiled (bytecode) files from .pyc to .pyo. See also PYTHONOPTIMIZE.

and

PYTHONOPTIMIZE

If this is set to a non-empty string it is equivalent
to specifying the -O option. If set to an integer, it is equivalent to
specifying -O multiple times.

Are asserts disabled in release build?

assert() in the <cassert> header is only disabled if you define the macro NDEBUG prior to including the <cassert> header file. See also these docs

With gcc/g++, the easiest way to do so is to define the NDEBUG macro on the command line when invoking the compiler like so:

g++ -DNDEBUG ... other args...

Arguments such as optimization flags and similar flags does not disable the assert.

How to turn off ASSERTs in debug mode in Visual Studio 2013

User _CrtSetReportMode

int iPrev = _CrtSetReportMode(_CRT_ASSERT,0);
// Start Operation with no ASSERTs
...
// Restore previous mode with ASSERTs
_CrtSetReportMode(_CRT_ASSERT,iPrev);

Instead of using 0, you can use _CRTDBG_MODE_DEBUG only.

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