split a string into an array of characters in vex

[WLVL]

I want to split a string after a specific number of characters.

ie. split after the 5th character (position 5)

string s = "0123456789";

into    

"012345" and "6789"

I don't have any consistent separator. I have a consistent amount of characters after which I want to split.

Split function won't work because by default it will set space as the separator if none is specified.

 

My approach would be.

Split the string into a characters array, and then recreate the separated strings using a for loop

string s_char[] => (0, 1, 2, 3 , 4, 5, 6 , 7, 8, 9)
int coord = 5; //coord to split at

string s_1, s_2;
for(int i; i <= coord; i++){
	s_1 += s_char[i];
}
for(int i; i>coord && i<max; i++){
	s_2 += s_char[i];
}

 

Any ideas on how to achieve this?

[ikoon]

Hi Davide, for strings and arrays, you can use the array[start:stop:step] syntax:

a[start:stop]  // items start through stop-1
a[start:]      // items start through the rest of the array
a[:stop]       // items from the beginning through stop-1
a[:]           // a copy of the whole array

For your case, this is the syntax:

int coord = 6;     // I changed the coord from 5 to 6
string s = "0123456789";

s@s_1 = s[:coord]; // "012345"
s@s_5 = s[coord:]; // "6789"

More examples and explanation here:

https://stackoverflow.com/questions/509211/understanding-slice-notation

a[-1]              // last item in the array
a[-2:]             // last two items in the array
a[:-2]             // everything except the last two items

//There is also the step value, which can be used with any of the above:
a[start:stop:step] // start through not past stop, by step

 

[acey195]

Yup array slicing is awesome ^^
I'm wondering though, for when I actually cast a string to a character array (or string array, as chars don't exist in hou)
it seems to error unfortunately.
Of course I could just loop through the entire string to build the array.. but is there also an elegant way to do it?


example of working, but "unelegant" code  :

string test = "Lorem ipsum";

int n = len(test);
string charArray[];
resize(charArray, n);

for(int i = 0; i < n; i++)
    charArray[i] = test[i];

printf("%s\n", charArray);

 

Edited August 29, 2022 by acey195