pdb\u5305
Python also includes a debugger to step through code. It is found in a module named pdb. This library is modeled after the gdb library for C. To drop into the debugger at any point in a Python program, insert the code:<\/p>\n\n\n\n
import pdb; pdb.set_trace()<\/strong> When this line is executed, it will present a (pdb) prompt, which is similar to the REPL. Code can be evaluated at this prompt and you can inspect objects and variables as well. Also, breakpoints can be set for further inspection.<\/p>\n\n\n\n Below is a table listing useful pdb commands:<\/p>\n\n\n\n Command Purpose IDLE\u8fd0\u884c\u5982\u4ee5\u4e0b\u4ee3\u7801\uff0c\u4f7f\u7528\u547d\u4ee4h,n,c,w,u,d,l\u6765\u8c03\u8bd5\u7a0b\u5e8f<\/p>\n\n\n\n
These are two statements here, but I typically type them in a single line separated by a semicolon\u2014that way I can easily remove them with a single keystroke from my editor when I am done debugging. This is also about the only place I use a semicolon in Python code (two statements in a single line).<\/p>\n\n\n\n
h, help List the commands available
n, next Execute the next line
c, cont, continue Continue execution until a breakpoint is hit
w, where, bt Print a stack trace showing where execution is
u, up Pop up a level in the stack
d, down Push down a level in the stack
l, list List source code around current line<\/p>\n\n\n\n# Fibonacci series up to n\r\nimport pdb; pdb.set_trace()\r\ndef fib(n):\r\n a, b = 0, 1\r\n while a < n:\r\n print(a, end=' ')\r\n a, b = b, a+b\r\n print()\r\n \r\nfib(1000)\r\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"