TLDR
Enter a command. For example: git show merged branches.

if

 
Performs conditional processing in shell scripts. See also: test, [. More information: https://www.gnu.org/software/bash/manual/bash.html#Conditional-Constructs.
 
  • Execute the specified commands if the condition command's exit status is zero:
     
    if {{condition_command}}; then {{echo "Condition is true"}}; fi
     
  • Execute the specified commands if the condition command's exit status is not zero:
     
    if ! {{condition_command}}; then {{echo "Condition is true"}}; fi
     
  • Execute the first specified commands if the condition command's exit status is zero otherwise execute the second specified commands:
     
    if {{condition_command}}; then {{echo "Condition is true"}}; else {{echo "Condition is false"}}; fi
     
  • Check whether a [f]ile exists:
     
    if [[ -f {{path/to/file}} ]]; then {{echo "Condition is true"}}; fi
     
  • Check whether a [d]irectory exists:
     
    if [[ -d {{path/to/directory}} ]]; then {{echo "Condition is true"}}; fi
     
  • Check whether a file or directory [e]xists:
     
    if [[ -e {{path/to/file_or_directory}} ]]; then {{echo "Condition is true"}}; fi
     
  • Check whether a variable is defined:
     
    if [[ -n "${{variable}}" ]]; then {{echo "Condition is true"}}; fi
     
  • List all possible conditions (test is an alias to [; both are commonly used with if):
     
    man [

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