In Scala, is there a way to take convert two lists into a Map? -


I have two lists, one list [a] and list [B] ] . What I need is map [A, B] , but if I need the terminology of zip then it started: 

  var tuplesOfAB = ListOfA zip listoff B

Now I'm not sure how a map from my tuplesOfAB to

a follow up As a question, I also want to overturn my map so that I map [B, A] with a map [A, B] .

2.8 Has anyone left me? What should be the type of result of the compiler to actually use CanBuildFrom functionality and using a type directive with the breakout :

<<>

will also do the following: 

  val n: map [A, B] = ( List a zip list B) (breakout)

and (as predicted, below, as mentioned) toMap 

  val O = (listA zip listB) .toMap

has been added to the library as You can: 

  val r = m.map (_ swap) (breakout): map [b, a]

Comments

Post a Comment

Popular posts from this blog

c++ - QtQuick: QQmlApplicationEngine failed to load component qrc:/main.qml:23 Invalid attached object assignment -

Looking at my thoughts below, am I barking the wrong tree? Or in the information given below, am I misusing the Qt API to get an error in the title? I'm trying to modify the sample to work with the default coefficic project generated from Qt Creator 3.3.0 (OpenSource). Qt 5.4.0 (GCC 4.6.1, 64bit) Based on. The first thing to look at after the code is that I stand by: The sample uses the main.cpp: qmlRegisterType & lt ; Squircle & gt; ("OpenGLUARMM", 1, 0, "Squircle"); QQuickView view; View.setResizeMode (QQuickView :: SizeRootObjectToView); View.setSource (QUrl ("QRC: ///scenegraph/openglunderqml/main.qml")); View.show (); Some name changes in my name. CPP qmlRegisterType & lt; Menuscreen & gt; ("OpenGLUnderQML", 1, 0, "Main Screen"); QQmlApplicationEngine engine; Engine.load (QUrl (QStringLiteral ("QRC: /main.qml"))); I'm not sure that the difference in using QQmlApplicationEngine...
Read more

sql - dynamically varied number of conditions in the 'where' statement using LINQ -

I am using my first project LINQ (in mvc), so maybe there's something very simple that I remember. However, a day of searching and experimenting does not work, so it works. I am trying to write a LINQ query (Linux to SQL) in which in many cases where the statement is different from an OR or an AND. We do not know how many conditions are going in the query till runtime. This search is for filter control, where the user can choose multiple criteria for filtering. Select from table where table.col = 1 or table.col = 2 or table.col = 7 .... 'Other number of conditions Before I just create the SQL query as a string, while looping over all the situations. However, it seems that there should be a good way to do this in LINQ. I tried to use Expression trees, but they had a second thought for this moment on my head, where the lambda function was to be executed inside the statement such as: values ​​for matchingRows = matchingRows for each value Where (function (row) row.c...
Read more

iphone - Smoothing a rounded stroke in Core Graphics -

I am making my own UITableViewCells with a gradient background. I have worked all the logic and drawing, but the one that I want to fix is ​​"chunky" around the corners of my custom cell: If you have corners, you See what I'm talking about. Here is the code that I am using to generate cells: CGCTXT C = UigRxGroupCertexConnect (); CGColorSpaceRef myColorSpace = CGColorSpaceCreateDeviceRGB (); CGGradientRef myGradient = Zero; CGFloat component [8] = TABLE_CELL_BACKGROUND; CGContextSetStrokeColorWithColor (C, [[UAColor colorWithWhite: 0.7 alpha: 1] CGColor]); CGContextSetLineWidth (C, 2); CGContextSetAllowsAntialiasing (C, Yes); CGContextSetShouldAntialias (C, Yes); CGFloat minx = CGRectGetMinX (RECT), MIDX = CGRactgetMIDX (RECT), MAX x = CGTXxX (RECT); CGFloat miny = CGRectGetMinY (Rect), maxy = CGRectGetMaxY (rect); CGMutablePathRef Path = CGPathCreateMutable (); CGPathMoveToPoint (path, NULL, minx, miny); CGPathAddArcToPoint (default margin of path, NULL, mix, ...
Read more