Small confusion in regex at | (pipe) -


when use pattren 

"(see|see also) [\w\d]+"

on text

see page  see page

but output matches is

see page  see

if im interchanged see, see also

"(see also|see) [\w\d]+"

the output 

see page  see page

i thought both same. may know why happen?

removing alternation , leaving see [\w\d]+ match string "see page" because satisfied see also. way regular expressions work alternation (at least in case) attempt match each option in order rest of pattern , stop successfully, or go alternatives when fails. when reverse alternation, tries match see also first, fail "see page."

it make more sense write see( also)? [\w\d]+


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