$ curl cheat.sh/
 cheat.sheets:source 
# source
# Execute commands from a file in the current shell

# This is a shell built-in, available within most if not all shells. However, -
# it may only be available as `.` in some older shells, such as Bourne shell.
# Its first argument is a file, with all proceeding arguments being parameters
# to the aforementioned file.

# Run shell code residing within FILE as though you'd entered it in yourself.
source FILE
# The above can be written in short-hand, for the same effect, shell allowing.
. FILE

#  Source FILE with the given arguments to said file.
source FILE Argument_1 Argument_2 Argument_3 ...

 tldr:source 
# source
# Execute commands from a file in the current shell.
# More information: <https://manned.org/source>.

# Evaluate contents of a given file:
source path/to/file

# Evaluate contents of a given file (alternatively replacing `source` with `.`):
. path/to/file

$
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