Checking if a file exists using a bash variable interpolated in a string

Question

In my bash profile, I currently have separate if statements to check if a file exists, and if it does, to execute it and load the corresponding variables into the shell environment:

# Aliases
if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
fi

# Functions
if [ -f ~/.bash_functions ]; then
    . ~/.bash_functions
fi

# Environment variables
if [ -f ~/.bash_variables ]; then
    . ~/.bash_variables
fi

This currently works just fine because the following files do indeed exist:

• ~/.bash_aliases
• ~/.bash_functions
• ~/.bash_variables

However, since all of these conditionals have shared logic, I'd like to do this instead:

modules=(aliases functions variables)
for module in ${modules[@]}; do
    bash_file="~/.bash_$module"
    echo "Loading $bash_file"
    if [ -f "$bash_file" ]; then
        . "$bash_file"
    fi
done

Unfortunately, this doesn't work.

When launching a new shell, I can confirm the following logs:

Loading ~/.bash_aliases
Loading ~/.bash_functions
Loading ~/.bash_variables

But for whatever reason, it seems that the file-checking logic is evaluating to false because none of my aliases/functions/variables load.

I've also tried:

• Using test -f "$bash_file".
• Removing quotes from around $bash_file.
• Quoting the elements of the array, even though this isn't necessary as far as I know.
• Replacing . with source, even though they're aliases.

What am I doing wrong?