String and text manipulation



Note: in the examples, some output  lines of the console were removed for clarity.


function! split  Red-by-example    MyCode4fun

Returnsblock (a series) containing the pieces of a string that are separated by a delimiter. Does not change original block. The delimiter is given as an argument. split is particularly useful to the parse dialect and to analyze and manipulate text files.

>> s: "My house is a very funny house"
>> split s " "                                                        ;every space is a delimiter.
== ["My" "house" "is" "a" "very" "funny" "" "" "" "" "house"] ;result is a series with 11 elements.

>> s: "My house ; is a very ; funny house"
>> split s ";"                                                        ;split happens at the semi-colons.
== ["My house " " is a very " " funny house"]        ;result is a series with 3 elements.

removing characters: action! trim  Red-by-example    MyCode4fun

The word trim with no refinements removes white space (tabs and spaces) from the beginning and end of a string! (it also removes none from a block! or object!). The value of the argument is altered. It has a refinement to remove specific characters. It returns the trimmed series and changes the original series.

Refinements:

/head - Removes only from the head.
/tail - Removes only from the tail.
/auto - Auto indents lines relative to first line.
/lines - Removes all line breaks and extra spaces.
/all - Removes all whitespace (but not line breaks).
/with - Same as /all, but removes characters in a 'with' argument we supply. It must be one of: char! string! or integer!

>> e: " spaces before and after "  
>> trim e
== "spaces before and after"

trim leading spaces:

>> e: " spaces before and after "
>> trim/head e
== "spaces before and after "

trim trailing spaces:

>> e: " spaces before and after "
>> trim/tail e
== " spaces before and after"

trim specific characters:

>> d: "our house in the middle of our street"
>> trim/with d " "
== "ourhouseinthemiddleofourstreet"

>> a: "house"
>> trim/with a "u"
== "hose"

the opposite of trim: function! pad  Red-by-example    

pad expands the string to a given size by adding spaces. The default is to add spaces to the right, but with the refinement /left , spaces are added to the beginning of the string. Changes the original string, beware.

>> a: "House"
>> pad a 10
== "House "

>> pad/left a 20
== " House "

text concatenation: function! rejoin  Red-by-example    MyCode4fun

>> a: "house" b: " " c: "entrance"
>> rejoin [a b c]
== "house entrance"

or, using append - this changes the original series

>> append a c
== "house entrance"

>> a: "house" b: " " c: "entrance"

>> append a c
== "houseentrance"

>> append a append b c
== "houseentrance entrance"                ; "a" was changed to "houseentrance" in the last manipulation

turning a series into text: action! form  Red-by-example    MyCode4fun

form returns a series as a string, removing brackets and adding spaces between elements. form was briefly seen in the Accessing and formating data chapter.

>> a: ["my" "house" 23 47 4 + 8 ["a" "bee" "cee"]]
>> form a
== "my house 23 47 4 + 8 a bee cee"

/part

The refinement /part limits the number of characters of the created string.

>> a: ["my" "house" 23 47 4 + 8 ["a" "bee" "cee"]]
>> form/part a 8
== "my house"

string length: action! length?  Red-by-example    MyCode4fun

>> f: "my house"
>> length? f        
== 8

left part of string:

using copy/part :

>> s: "nasty thing"
>> b: copy/part s 5
== "nasty"

right part of string:

using at :

>> s: "nasty thing"
>> at tail s -5
== "thing"

using remove/part - this changes the original series, beware!

>> s: "nasty thing"
>> remove/part s 6
== "thing"

middle part of string:

using copy/part and at:

>> a: "abcdefghijkl"
>> copy/part at a 4 3
== "def"

insert strings:

at the beginning, using insert:

>> s: "house"
>> insert s "beautiful "

>> s
== "beautiful house"

at the end, using append:

>> s: "beautiful"
>> append s " day"
== "beautiful day"

in the middle, using insert at:

>> s: "nasty thing"
>> insert at s 7 "little "

>> s
== "nasty little thing"

native! lowercase  Red-by-example    MyCode4fun

Changes the original string, beware.

>> a: "mY HoUse"
>> lowercase a
== "my house"

/part

>> a: "mY HoUse"
>> lowercase/part a 2
== "my HoUse"

native! uppercase  Red-by-example    MyCode4fun

Changes the original string, beware.

>> a: "mY HoUse"
>> uppercase a
== "MY HOUSE"

/part

>> a: "mY HoUse"
>> uppercase/part a 2
== "MY HoUse"


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