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### Definitions
    "ugly characters"   ;; chars either not allowed or desired
    "too long"          ;; maximum allowable length for a basename
    "basename"          ;; file-full-path minus file-extension
    "file-extension"    ;; anything that satisfies m/\.[^\.]+$/
    "rename suprises"   ;; unexpected results from a batch rename

### standard operations
    rename extension    (eg *.foo to *.fee)
    rename basename     (eg ibm*.* to IBM*.*)
    routine replace     (eg lower-case to upper-case)

### file-management operations
    rename and move
    rename and copy
    rename to non-yet-existent location (mkpath-style)

### scrubbing operations
    remove  all "ugly characters"
    replace all "ugly characters" with a safe char (eg "_")
    reduce  all "too long" names to a truncated shorter name
        (and allow the user to specify truncate rules)
        (and prevent "rename collision" on non-unique truncations)

### safeguard operations
    avoid "rename collision" by halting the program
    avoid "rename collision" by appending UniqueID
    avoid "rename suprises"  with global-preview-before-rename

### rename based on content
    rename htm file by the content of the <title> tag
        (and apply all scrubbing operations)
        (and skip the rename if already been done before)
    rename htm file by some UniqueID if no <title> tag exists

### rename based on context
    rename to include all directory-path-steps as part of the name
    rename to include the last 2 path-steps as part of the name


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