if let Some(origin) = resp.get(“origin”) { // use origin } If you can guarantee that it’s impossible for the value to be None, then you can use: let origin = resp.get(“origin”).unwrap(); Or: let origin = resp.get(“origin”).expect(“This shouldn’t be possible!”); And, since your function returns a Result: let origin = resp.get(“origin”).ok_or(“This shouldn’t be possible!”)?; Or with … Read more
This is exactly why I wrote these functions, which are apparently impressively obscure since nobody has mentioned them. scala> import PartialFunction._ import PartialFunction._ scala> cond(“abc”) { case “def” => true } res0: Boolean = false scala> condOpt(“abc”) { case x if x.length == 3 => x + x } res1: Option[java.lang.String] = Some(abcabc) scala> condOpt(“abc”) … Read more
First, aren’t you supposed to be using vl_sift instead of sift? Second, you can use SIFT feature matching to find correspondences in the two images. Here’s some sample code: I = imread(‘p1.jpg’); J = imread(‘p2.jpg’); I = single(rgb2gray(I)); % Conversion to single is recommended J = single(rgb2gray(J)); % in the documentation [F1 D1] = vl_sift(I); … Read more
Before you read on, have you looked at biopython? It appears that you want to find approximate matches with one substitution error, and zero insertion/deletion errors i.e. a Hamming distance of 1. If you have a Hamming distance match function (see e.g. the link provided by Ignacio), you could use it like this to do … Read more
A jump table is used, making the pattern-match a constant time operation. Unfortunately I’m unable to find an up-to-date citation for this, although this page mentions the implementation of Cmm-level switch statements as jump tables, and this old tagging design document uses a case on a Bool as an example, producing a jump table.
Since self is of type &mut Self, it is enough to match against itself, while omitting ref entirely. Either dereferencing it with *self or adding & to the match arm would cause an unwanted move. fn ref_mut(&mut self) -> &mut i32 { match self { OwnBox(i) => i, } } For newtypes such as this … Read more
You can Use $options => i for case insensitive search. Giving some possible examples required for string match. Exact case insensitive string db.collection.find({name:{‘$regex’ : ‘^string$’, ‘$options’ : ‘i’}}) Contains string db.collection.find({name:{‘$regex’ : ‘string’, ‘$options’ : ‘i’}}) Start with string db.collection.find({name:{‘$regex’ : ‘^string’, ‘$options’ : ‘i’}}) End with string db.collection.find({name:{‘$regex’ : ‘string$’, ‘$options’ : ‘i’}}) Doesn’t … Read more
You need a “non-equi” or “range” join. This is implemented in fuzzyjoin and data.table packages for R. Since it is also supported in SQL, one can also use sqldf. Sadly, dplyr does not support this natively. Since this action is supported in SQL, if your data are in a database then dbplyr would allow it … Read more
Like @a_horse commented, you would have to use the regular expression operator ~ to use bracket expressions. But there’s more. I suggest: SELECT * FROM tbl WHERE value ~ ‘^00[^0]’ ^ … match at start of string (your original expression could match at any position). [^0] … a bracket expression (character class) matching any character … Read more
Ant-style path patterns matching in spring-framework: The mapping matches URLs using the following rules: ? matches one character * matches zero or more characters ** matches zero or more ‘directories’ in a path {spring:[a-z]+} matches the regexp [a-z]+ as a path variable named “spring” Some examples: com/t?st.jsp – matches com/test.jsp but also com/tast.jsp or com/txst.jsp … Read more