2. Cleaning and transforming

Text from a file or from a user is rarely clean. The header of the table of report arrives with blanks everywhere.

Blanks

header = '   year,   make , model,price   '
print '(A)', '['//header//']'
header = header%strip()                           ! blanks at both ends
print '(A)', '['//header//']'
header = header%replace(old=' ', new='')          ! every blank
print '(A)', '['//header//']'
print '(A)', '['//header%upper()//']'

• strip removes the blanks at both ends.
• replace substitutes every occurrence of old with new; an empty new deletes.
• upper (and lower) change the case.

Words

note = 'a   small  city car'
note = note%unique(' ')                           ! runs of blanks collapsed to one
print '(A)', note%startcase()//''
print '(A)', note%snakecase()//''
print '(A)', note%camelcase()//''
print '(A)', note%capitalize()//''

unique collapses every run of a repeated substring to one occurrence. startcase, snakecase and camelcase split the string in words and rewrite them in a style; capitalize makes upper case the first character only.

A set of characters

note = '** sold **'
print '(A)', '['//note%strip(remove='* ')//']'    ! a set of characters to remove

With remove, strip removes from both ends every character of a set, in any order they occur.

Whitespace, repeats, character sets

note = '  ac'//achar(9)//'abs   moon  '
print '(A)', '['//note%compact()//']'              ! whitespace runs to one blank, the ends removed
note = 'extended edition!!! ...'
print '(A)', note%squeeze(set='!.')//''           ! runs of these characters reduced to one
note = 'E350'
print '(A)', note%transliterate('0123456789', '#')//''  ! every digit becomes a '#'

• compact turns every run of whitespace, blanks, tabs or new lines, into one blank and removes it at both ends.
• squeeze reduces every run of a repeated character to one; with set, only for the characters of the set.
• transliterate replaces each character of a set by the one at the same position in another set; a shorter second set repeats its last character, an empty one deletes.

Running it

$ report
[   year,   make , model,price   ]
[year,   make , model,price]
[year,make,model,price]
[YEAR,MAKE,MODEL,PRICE]
A Small City Car
a_small_city_car
ASmallCityCar
A small city car
[sold]
[ac abs moon]
extended edition! .
E###

The whole program:

program report
!< Tutorial, chapter 2: cleaning and transforming.
use stringifor
implicit none
type(string) :: header, note

header = '   year,   make , model,price   '
print '(A)', '['//header//']'
header = header%strip()                           ! blanks at both ends
print '(A)', '['//header//']'
header = header%replace(old=' ', new='')          ! every blank
print '(A)', '['//header//']'
print '(A)', '['//header%upper()//']'

note = 'a   small  city car'
note = note%unique(' ')                           ! runs of blanks collapsed to one
print '(A)', note%startcase()//''
print '(A)', note%snakecase()//''
print '(A)', note%camelcase()//''
print '(A)', note%capitalize()//''

note = '** sold **'
print '(A)', '['//note%strip(remove='* ')//']'    ! a set of characters to remove

note = '  ac'//achar(9)//'abs   moon  '
print '(A)', '['//note%compact()//']'              ! whitespace runs to one blank, the ends removed
note = 'extended edition!!! ...'
print '(A)', note%squeeze(set='!.')//''           ! runs of these characters reduced to one
note = 'E350'
print '(A)', note%transliterate('0123456789', '#')//''  ! every digit becomes a '#'
endprogram report

What you learned

strip, replace, unique, the case methods; compact, squeeze, transliterate. Each returns a new string: assign it back to change the variable. Reference: String Manipulation.

Next: 3. Splitting and joining.