🕸📝Fergus Duniho wrote on Sat, Jan 7, 2017 02:50 AM UTC:
I have just created a new function called filter. Like aggregate, it takes a lambda function and an array as arguments, and it returns an array. Unlike aggregate, it returns both the key and the value of any array element for which the Lambda function evaluates as true, and it can use both the key and the value in the Lambda function. In the Lambda function, #0 stands for the key, #1 for the value. When the value is an array, #1 is the first element in the array, #2 the second, and so on. While aggregate returns the value of the Lambda function for each true call of it, filter just returns the key and value from the original array. So there is no need to include the return value in the Lambda function when using filter. So, you can ignore what I said in my last message and make these substitutions in your code:
Instead of onlyupper, use "filter lambda (isupper char #1 0) pieces"
Instead of onlylower, use "filter lambda (islower char #1 0) pieces"
If you use any piece labels that do not begin with an alphabetic character, these will work better:
Instead of onlyupper, use "filter lambda (fnmatch "*[A-Z]*" #1) pieces"
Instead of onlylower, use "filter lambda (fnmatch "*[a-z]*" #1) pieces"
I also created a regmatch function, which you can use if you are familiar with regular expressions. It works like fnmatch except that the first argument should be a regular expression instead of a wildcard pattern.
Instead of onlyupper, use "filter lambda (regmatch "/[A-Z]/" #1) pieces"
Instead of onlylower, use "filter lambda (regmatch "/[a-z]/" #1) pieces"
For the friend functions, you can use what I already gave you, or you can use one of these pairs:
I have just created a new function called filter. Like aggregate, it takes a lambda function and an array as arguments, and it returns an array. Unlike aggregate, it returns both the key and the value of any array element for which the Lambda function evaluates as true, and it can use both the key and the value in the Lambda function. In the Lambda function, #0 stands for the key, #1 for the value. When the value is an array, #1 is the first element in the array, #2 the second, and so on. While aggregate returns the value of the Lambda function for each true call of it, filter just returns the key and value from the original array. So there is no need to include the return value in the Lambda function when using filter. So, you can ignore what I said in my last message and make these substitutions in your code:
Instead of onlyupper, use "filter lambda (isupper char #1 0) pieces"
Instead of onlylower, use "filter lambda (islower char #1 0) pieces"
If you use any piece labels that do not begin with an alphabetic character, these will work better:
Instead of onlyupper, use "filter lambda (fnmatch "*[A-Z]*" #1) pieces"
Instead of onlylower, use "filter lambda (fnmatch "*[a-z]*" #1) pieces"
I also created a regmatch function, which you can use if you are familiar with regular expressions. It works like fnmatch except that the first argument should be a regular expression instead of a wildcard pattern.
Instead of onlyupper, use "filter lambda (regmatch "/[A-Z]/" #1) pieces"
Instead of onlylower, use "filter lambda (regmatch "/[a-z]/" #1) pieces"
For the friend functions, you can use what I already gave you, or you can use one of these pairs:
fnmatch "*[A-Z]*" #0
fnmatch "*[a-z]*" #0
regmatch "/[A-Z]/" #0
regmatch "/[a-z]/" #0