Get current line python

Get the Current Line Number in Python: Tips and Tricks

Learn how to get the current line number in Python with tips and tricks using built-in functions like inspect, enumerate, find, and linecache modules.

• Using the inspect module
• Using the enumerate function
• Python: Using the inspect module to get line numbers and other
• Using the find function
• Using the linecache module
• Other helpful tips and tricks
• Other helpful code examples for getting the current line number in Python
• Conclusion
• How do you find the line number of a string in Python?
• How do I find the line number in a file?
• How do you get line numbers in Python idle?
• How do I print a specific line from a file in Python?

Python is a popular programming language that is widely used for data science, machine learning, and web development. If you are working with Python, you may need to know how to get the current line number in your code. In this blog post, we will explore several ways to get the current line number in Python and some helpful tips and tricks for working with python.

Using the inspect module

The inspect module in python provides several functions for debugging and introspection. One of these functions is the currentframe function, which returns the current frame object. By using the frameinfo function on the current frame object, you can get information about the current frame, including the filename and line number.

The inspect module is a built-in module in Python, so you don’t need to install any additional packages to use it. Here is an example of how to use the inspect module to get the current line number in Python:

import inspectdef foo(): print("Current line number:", inspect.currentframe().f_lineno)foo() 

In this example, we define a function called foo that prints the current line number using the inspect module. We then call the foo function to print the current line number.

The currentframe function returns the current frame object, which represents the stack frame for the current function call. The frameinfo function returns information about the current frame, including the filename and line number.

Using the enumerate function

The enumerate function in python is used to loop over a sequence and return an enumerated list. By using the enumerate function on a file opened in Python, you can get the line number of each line in the file. You can also use the start parameter to specify the starting line number.

Here is an example of how to use the enumerate function to get the current line number in Python:

with open("example.txt") as f: for i, line in enumerate(f, start=1): print("Line <>: <>".format(i, line)) 

In this example, we open a file called example.txt and use the enumerate function to loop over each line in the file. We use the start parameter to specify that the line numbers should start at 1.

Python: Using the inspect module to get line numbers and other

I show how to write a function to get the line number, source file name, and function name with Duration: 8:46

Using the find function

If you need to find the line number of a specific phrase in a file, you can use the find function in Python. The find function returns the index of the first occurrence of the specified phrase in the file. By using the count function on the file up to the specified phrase, you can get the line number of the specified phrase.

Here is an example of how to use the find function to get the current line number in Python:

with open("example.txt") as f: text = f.read()index = text.find("example phrase") line_number = text.count("\n", 0, index) + 1print("Line number:", line_number) 

In this example, we open a file called example.txt and read its contents into a variable called text . We then use the find function to find the index of the first occurrence of the phrase “example phrase” in the file. We use the count function to count the number of newline characters ( \n ) in the file up to the specified index, which gives us the line number of the specified phrase.

Using the linecache module

The linecache module in python is used to cache lines from files for quick access. By using the getline function on a file opened in Python, you can print a specific line from the file. You can also use the getframeinfo function on a running Python process to get the filename and line number of the current frame.

Here is an example of how to use the linecache module to get the current line number in Python:

import linecachefilename = "example.txt" line_number = 5line = linecache.getline(filename, line_number)print("Line <>: <>".format(line_number, line.strip())) 

In this example, we define a filename and a line number and use the getline function from the linecache module to get the contents of the specified line from the file. We use the strip method to remove any extra whitespace from the line.

Other helpful tips and tricks

There are several other helpful tips and tricks for working with Python. For example, you can use the wc command to find the number of lines in a file. You can also show line numbers in Python idle by going to Options and clicking Show Line Numbers. Additionally, you can use the co_firstlineno expression to get the line number of a function in Python.

The wc command is a command-line tool for counting words, lines, and characters in a file. You can use it like this:

This command will print the number of lines in the file example.txt .

To show line numbers in Python idle, go to Options and click Show Line Numbers. This will add line numbers to the left of each line in the editor.

Finally, you can use the co_firstlineno expression to get the line number of a function in Python. Here is an example:

def foo(): print("Current line number:", foo.__code__.co_firstlineno)foo() 

In this example, we define a function called foo and use the co_firstlineno expression to get its line number.

Other helpful code examples for getting the current line number in Python

In python, python how to get current line number code example

#python3 from inspect import currentframe, getframeinfoframeinfo = getframeinfo(currentframe())print(frameinfo.filename, frameinfo.lineno) 

In python, how to get the current line number in python code example

from inspect import currentframedef get_linenumber(): cf = currentframe() return cf.f_back.f_linenoprint "This is line 7, python says line ", get_linenumber()

Conclusion

In this blog post, we have explored several ways to get the current line number in Python. By using the inspect module, the enumerate function, the find function, and the linecache module, you can easily get the current line number in your Python code. Additionally, we have provided some helpful tips and tricks for working with python. We hope that this blog post has been informative and helpful for you.

Frequently Asked Questions — FAQs

How do I get the current line number in Python using the inspect module?

You can use the currentframe function from the inspect module to get the current frame object. By using the frameinfo function on the current frame object, you can get information about the current frame, including the filename and line number.

Can I use the enumerate function to get the line number of each line in a file?

Yes, you can use the enumerate function on a file opened in Python to get the line number of each line in the file.

How can I find the line number of a specific phrase in a file using Python?

You can use the find function in Python to find the index of the first occurrence of the specified phrase in the file. By using the count function on the file up to the specified phrase, you can get the line number of the specified phrase.

How does the linecache module help in getting the current line number in Python?

The linecache module in Python is used to cache lines from files for quick access. By using the getline function on a file opened in Python, you can print a specific line from the file. You can also use the getframeinfo function on a running Python process to get the filename and line number of the current frame.

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Get current line python

is there a way to get the source file line number in some code? for example:

from __future__ import print_function # print a message with source line number n = get_source_code_file_line_number() n += 2 print('now printing at line',str(n))

Output:
now printing at line 6

from __future__ import print_function for n in range(3) print('now printing at line',str(get_source_code_file_line_number())) print('now printing at line',str(get_source_code_file_line_number()))

Output:
now printing at line 2 now printing at line 3 now printing at line 2 now printing at line 3 now printing at line 2 now printing at line 3

Tradition is peer pressure from dead people

What do you call someone who speaks three languages? Trilingual. Two languages? Bilingual. One language? American.

Larz60+
aetate et sapientia

i mean at run time
i found this solution that seems to work:

import inspect print( 'line', inspect.getframeinfo(inspect.currentframe()).lineno, 'of file', inspect.getframeinfo(inspect.currentframe()).filename )

Tradition is peer pressure from dead people

What do you call someone who speaks three languages? Trilingual. Two languages? Bilingual. One language? American.

snippsat

Yes can use inspect for this.
Can make a function,then insert that function call will print line number.

import inspect def line_numb(): '''Returns the current line number in our program''' return inspect.currentframe().f_back.f_lineno # print a message with source line number n = 2 ; print('variable <> is at line <>'.format(n, line_numb())) print('now printing at line <>'.format(line_numb()))

Output:
variable 2 is at line 8 now printing at line 9

(Feb-27-2017, 03:29 AM) snippsat Wrote: Yes can use inspect for this.
Can make a function,then insert that function call will print line number.

import inspect def line_numb(): '''Returns the current line number in our program''' return inspect.currentframe().f_back.f_lineno # print a message with source line number n = 2 ; print('variable <> is at line <>'.format(n, line_numb())) print('now printing at line <>'.format(line_numb()))

Output:
variable 2 is at line 8 now printing at line 9

this also gives me the solution to another long time problem: a function to display the name and value of a variable, given only one argument . a string of the name (so a coding error by the user of this function cannot result in a mismatch)

from inspect import currentframe from os import environ def v(n): if 'nodebug' in environ: return x=currentframe().f_back.f_locals if n not in x: return print(n,'not assigned') return print(n,'=',repr(x[n]))

edit: correction applied to code: s/[0]//

Tradition is peer pressure from dead people

What do you call someone who speaks three languages? Trilingual. Two languages? Bilingual. One language? American.

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