[education/rkward] rkward/syntax: Update syntax test file

[Thomas Friedrichsmeier]

Git commit 9c47c880a7026ae0d805a38896f7451393cef57c by Thomas Friedrichsmeier.
Committed on 07/05/2023 at 09:45.
Pushed by tfry into branch 'master'.

Update syntax test file

M  +71   -33   rkward/syntax/r-syntax-test.R

https://invent.kde.org/education/rkward/commit/9c47c880a7026ae0d805a38896f7451393cef57c

diff --git a/rkward/syntax/r-syntax-test.R b/rkward/syntax/r-syntax-test.R
index 9657a22aa..4cef16dab 100644
--- a/rkward/syntax/r-syntax-test.R
+++ b/rkward/syntax/r-syntax-test.R
@@ -1,14 +1,30 @@
+## R syntax test/demo file
+# constructs that are (syntactically) illegal are commented as "syntax error")
+# instances of known wrong highlighting (at the time of this writing) are commented as "BUG"
+# instances of questionable highlighting, without an obvious desirable bevhior are commented as "CORNER CASE"
+
 ## This is a Headline
 # This is a Comment
 
-myBoolean <- TRUE
+# data types
+myBoolean <- c(TRUE, FALSE)
 myNa <- NA
+myFloat <- 1.234
+myInt <- 1l
 
-myString <- "This is a String"
-"String 2" -> myString2
-myString3 <<- "global assignment"
-myString4 <- as.character( 3 + 4 )
+# quotes:
+cat ("normal quote", 'single quoted', "with escapes \" and newline \n' ", 'with escapes and newline 2 \'\n" ')
+`backquoted symbol name` <- 1
+"backquoted symbol name"        # This will print the string
+`backquoted symbol name`        # This will print the value (1)
+cat( "\nNo Errors!\n" )
 
+# assignments and operators
+myString <- "regular assignment"
+"assignment to the right" -> myString2
+myString3 <<- "global assignment"
+"global assignment to the right" ->> myString4
+myString5 <- as.character( 3 + 4 )
 myMatrix  <- matrix( 1:6, nrow = 3, ncol = 2 )
 myMatrix2 <- myMatrix + 4
 myMatrix3 <- t( myMatrix ) %*% myMatrix
@@ -16,6 +32,31 @@ myMatrix[ myMatrix < 4 ] <- 0
 myMatrix[ myMatrix == 4 ] <- 10
 myFloat = 1.234
 myBooleanVector <- c( 1, 5 ) %in% c( 1, 2, 3, 4 )
+formula(a~b+c)
+
+# subsetting
+myClass at mySlot
+myList$myItem
+myList[["myItem"]]
+myList[varHoldingItemName, ]
+
+# named arguments
+myList <- list( a = 1, a2 = 2, a2_b = 3, _a3=4 )
+print ("hi", quote=(x==1))
+x = list(x=1)        # note the different highlighting between '=' used for assignment and for named arugment
+x <- list(a <- 1)    # this is syntactically legal (but both '<-'s will creeate local objects; 'a' will not become an argument name)
+myList <- list(2a = 2) # illegal argument name
+myList <- list(_a = 2) # syntax error: illegal argument name (BUG)
+myList <- list(a=1, 
+               b=2)    # function call spanning multiple lines
+
+0# Base R pipeline (since R 4.1.0)
+x <- rnorm(1000) |> round() |> max()
+# CORNER CASE: as of R 4.2.0, "=>" has to be enabled, explicitly
+rnorm(1000) |> round() |> max() |> d => seq(from = 1, to = d)
+
+# magrittr pipes (no special highlighting needed, as these are just infix operators)
+rnorm(1000) %>% round() %>% max() %>% seq(from = 1, to = .)
 
 if( 3 > 4 ) {
    stop( "Error: 3 is not graeter than 4!!!" )
@@ -24,38 +65,35 @@ if( 3 > 4 ) {
 }
 
 for( i in 2:5 ) {
+   x <- i
    print( paste( "No. ", as.character( i + ( 3 + i ) ), sep = "" ) )
+   while(x == i) {
+     print(paste("Nested", "expression"))
+     x <- i+1
+   }
 }
+x in 1:3  # CORNER CASE: "in" is only valid inside for statement
 
+# corner cases and illegal constructs
 try ( {
-	x <<- 1
-	x <<<- 1		# syntax error
-	x <- * 1		# syntax error
-	x += 1 -= x1 *= x2	# syntax error
-	x =* 1 =/ x1 // x2	# syntax error
-	x +!= y +-= z +!/ 2	# syntax error
-	x =+ 1 =- x1		# These look misleading, but are legal
-	1 +-!-++--!!+ 1		# Crazy, but legal
-	x <- ~1			# ERROR: Actually, this is legal, but it's marked up as an error
-	"%my 1st infix%" <- function (x, y) { x + y }		# legal infix
+	x <<<- 1                 # syntax error
+	x <- * 1                 # syntax error
+	x += 1 -= x1 *= x2       # syntax error
+	x =* 1 =/ x1 // x2       # syntax error
+	x +!= y +-= z +!/ 2      # syntax error
+	x |< print()             # syntax error
+	x =+ 1; x =- x1; x <-- 1 # These look misleading, but are legal
+	1 +-!-++--!!+ 1          # Crazy, but legal
+
+	x <- ~1                 # BUG: Actually, this is legal (if uncommon), but it's marked up as an error
+
+	"%my 1st infix%" <- function (x, y) { x + y }   # create a legal (uncommon) infix
 	3 %my 1st infix% 4
-	"%my%infix%" <- function (x, y) { x + y }	# illegal infix
-	3 %my%infix% 4					# syntax error
-	3 %my%infix%other% 4				# but could be continued to something syntactically legal
-	)		# unexpected closing ')'
-	(})		# unexpected closing '}'
+	"%my%infix%" <- function (x, y) { x + y }       # create an illegal infix
+	3 %my%infix% 4                                  # syntax error
+	3 %my%infix%other% 4                            # but could be continued to something syntactically legal
+	)                       # syntax error: unexpected closing ')'
+	(})                     # syntax error: unexpected closing '}'
+	]                       # syntax error: unexpected closing ']' (BUG)
 },
 silent=FALSE)
-
-myList <- list( a = 1, a2 = 2, a2_b = 3 )
-
-x <- 1
-print ("hi", quote=(x==1))
-
-# quotes:
-cat ("normal quote", 'single quoted', "with escapes \" ' ", 'with escapes 2 \' " ')
-`backquoted symbol name` <- 1
-"backquoted symbol name"	# This will print the string
-`backquoted symbol name`	# This will print the value (1)
-
-cat( "\nNo Errors!\n" )