reducing the number of try,except in python

Question

I'm writing a program similar to a diagnostic program , that runs a test and then based on that do more tests, so most of these are done inside `try,except and there are quite a lot of them. Is there any other way to achieve this but reduce the number of try except?

Here is a sample code.

try:
    treeinfo = subprocess.check_output(['C:\Python27\Scripts\scons.bat','-f' ,'scons_default.py' ,'--tree=all'])
    print "\n"
    print "Your machine type is ",platform.machine()
        print "Compiling using default compiler\n"
    print treeinfo

except subprocess.CalledProcessError as e:
    print "ERROR\n"

try:
    with open ('helloworld.exe')as f:
        subprocess.call('helloworld.exe')
        print"Build success"
        log64 =  subprocess.check_output(["dumpbin", "/HEADERS", "helloworld.exe"])
        if arch64 in log64:
            print "Architecture of the compiled file is 64-bit "
        elif arch32 in log64:
            print "Architecture of the compiled file is 32-bit"
except IOError as e:
    print "Build failed\n"


print "\n"

The same code above (with different file names) repeat and I know that it's not a good practice to do that. I'm pretty new to python and googling didn't give any helpful results.

Answer 1

You can split your logic into separate functions and call them one by one in a try block:

def a():
    treeinfo = subprocess.check_output(['C:\Python27\Scripts\scons.bat','-f' ,'scons_default.py' ,'--tree=all'])
    print "\n"
    print "Your machine type is ",platform.machine()
    print "Compiling using default compiler\n"
    print treeinfo

def b():
    subprocess.call('helloworld.exe')
    print"Build success"

def c():
    log64 =  subprocess.check_output(["dumpbin", "/HEADERS", "helloworld.exe"])
    if arch64 in log64:
        print "Architecture of the compiled file is 64-bit "
    elif arch32 in log64:
        print "Architecture of the compiled file is 32-bit"

def try_these(funs, catch):
    for fun in funs:
        try:
            fun()
        except catch:
            print 'ERROR!'

try_these([a, b, c], catch=(IOError, OSError))

where "catch" a tuple of exceptions you want to handle.