# No args is an error
argparse: No option specs were provided
# Missing -- is an error
argparse: Missing -- separator
# Flags but no option specs is an error
argparse: No option specs were provided
# Invalid option specs
argparse: Invalid option spec 'h-' at char '-'
argparse: Short flag '+' invalid, must be alphanum or '#'
argparse: Invalid option spec 'h/help:' at char ':'
argparse: Invalid option spec 'h-help::' at char ':'
argparse: Invalid option spec 'h-help=x' at char 'x'
# --max-args and --min-args work
min-max: Expected at least 1 args, got only 0
min-max: Expected at most 3 args, got 4
min-max: Expected at most 1 args, got 2
# Invalid "#-val" spec
argparse: Implicit int short flag '#' does not allow modifiers like '='
# Invalid arg in the face of a "#-val" spec
argparse: Unknown option '-x'
Standard input (line 38): 
argparse '#-val' -- abc -x def
^
# Defining a short flag more than once
argparse: Short flag 's' already defined
# Defining a long flag more than once
argparse: Long flag 'short' already defined
# Defining an implicit int flag more than once
argparse: Implicit int flag '#' already defined
# Defining an implicit int flag with modifiers
argparse: Implicit int short flag 'v' does not allow modifiers like '='