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stringlualua-patterns

check that string starts and ends with a specific pattern in Lua

I have a table which is having string values 

data_table = {'(?P<smartcache>.+)$', 'css', '123454', '(?P<version>.+)$'}

I am trying to see if a string startswith '(?P<' and endswith ')$' . I want a string in output which will be like

output_table = '/smartcache/css/123454/version'

I am facing problem to fetch values which are passed with patterns like I want to fetch 'smartcache' from (?P<smartcache>.+)$.

My Try:

out_string_value = (string.match(uri_regex, '[^(?P<].+[)$]')

here I am getting output as smartcache>.+)$ but I want smartcache.

Solution 
  • local uri_regex = '(?P<smartcache>.+)$'
local out_string_value = uri_regex:match('^%(%?P<([^>]+)>.*%)%$$')
print(out_string_value)

    The Lua pattern ^%(%?P<([^>]+)>.*%)%$$ is similar to the regex ^\(\?P<([^>]+)>.*\)\$$ except that Lua pattern uses % to escape magic characters.