Deprecated elsif, new "chaining" syntax

README.md

@@ -55,7 +55,7 @@ Zrc is just ~600KB in size because its implementation is to the point and simple
 		- [X] Return value (`[...]`)
 - [X] Built-in commands (like `expr`, `jobs`, etc. but there are too many to list. View `dispatch.hpp`)
 - [X] Conditional logic/flow control with full C arithmetic operator set
-	- [X] If/elsif/else
+	- [X] If/else
 	- [X] Do
 	- [X] While
 	- [X] Foreach

doc/man1/expr.1

@@ -37,7 +37,7 @@ which writes to stdout, so square brackets should be used to access it.
 .RB * , / , // , % ;
 .SS Precedence level 13: implicit
 .SS Functions
-.RB log10 , log2 , log , sqrt , sin , cos , ctg , tg , floor , ceil , abs;
+.RB log10 , log2 , log , sqrt , sin , cos , ctg , tg , floor , ceil , abs , round;
 .SS Other words
 .RB nan , false , true ;
 .SS Unary operators

doc/man1/fn.1

@@ -15,24 +15,20 @@ Alternatively, you can trap a signal by defining a function with the name of tha
 	fn is_prime {
 		if {$argv(1) < 2} {
 			return 0
-		} elsif {$argv(1) == 2) {
+		} else if {$argv(1) == 2} {
 			return 1
-		} elsif {$argv(1) % 2 == 0} {
+		} else if {$argv(1) % 2 == 0} {
 			return 0
-		} else {
-			let {i ok} {
-				set ok = 1
-				for {set i = 3} {$i <= $argv(1)/2} {inc i} {
-					if {$argv(1) % $i == 0} {
-						set ok = 0
-						set i = $argv(1)
-					}
+		} else let i {
+			for {set i = 3} {$i <= $argv(1)/2} {inc i} {
+				if {$argv(1) % $i == 0} {
+					return 0
 				}
-				return $ok
 			}
+			return 1
 		}
 	}
-
+	
 	##################
 	# Trap SIGWINCH. #
 	##################

doc/man1/if.1

@@ -2,25 +2,24 @@
 .SH NAME
 if \- Execute script body if a condition is met
 .SH SYNOPSIS
-.BI "if " "<expr> <block>" " [elsif " "<expr> <block>..." "|else " <block> ]
+.BI "if " "<expr> <block>" " [else " "< <block>" | "<w1> <w2>...<wn> >" ]
 .SH DESCRIPTION
 The
 .I if
 command evaluates its first argument as an 'expr' expression and executes the second argument as a script if said expression is true. If it is not true, it checks the next argument. If it is
-.BR elsif ,
-it evaluates the argument next to it as an expression and executes another function body, otherwise if it is
-.BR else
-ii evaluates the argument next to it regardless of an expression. This can repeat for as many times as necessary.
+.BR else ,
+it either evaluates one single argument as a script, or treats its remaining arguments as words for a new command to be exec'd via Bernstein chaining (NOT evaled!).
 .SH EXAMPLE
 .EX
 	set i = 0
-	if {i == -2} { 
+	if {$i == -2} { 
 		echo this shouldn\\'t happen
-	} elsif {i == -1} {
+	} else if {$i == -1} {
 		echo elsif test
-	} elsif {i > 0} {
+	} else if {$i > 0} {
 		echo elsif test \\# 2
-	} else {
-		echo 0 equals 0 true
+	} else while {$i < 10} {
+		echo '$i < 10'
+		set i += 1
 	}
 .EE

doc/man1/zrc.1

@@ -330,7 +330,7 @@ Looping construct #3.
 .br
 List all commands.
 .HP
-.BI "if " "<expr> <block>" " [elsif " "<expr> <block>..." "|else " <block> ]
+.BI "if " "<expr> <block>" " [else " "< <block>" | "<w1> <w2>...<wn> >" ]
 .br
 Conditional statement #1.
 .HP

examples/bernstein_chaining.zrc

@@ -0,0 +1,17 @@
+#!../bin/zrc
+set i = 0
+read -p "What to do? (0, 1, 2 or something else) " x
+
+if {$x == 0} {
+	ls | wc -mlw
+	cd ~/
+} else {
+	if {$x == 1} {
+		echo 'You entered 1!'
+	} else if {$x == 2} {
+		echo 'You entered 2!'
+	} else while {$i < 10} {
+		echo $i
+		inc i
+	}
+}

examples/quicksort.zrc

@@ -29,11 +29,7 @@ fn quicksort {
 			}
 			set $vn = '$$vn $x'
 		}
-		return [concat \
-			[quicksort $less] \
-			$equal \
-			[quicksort $greater]
-		];
+		return [concat [quicksort $less] $equal [quicksort $greater]]
 	}
 }
 

examples/server.zrc

@@ -72,24 +72,24 @@ fn remo {
 		ssh-agent -k &
 
 	#2:
-	} elsif {[string cmp $argv(1) "dialog"] == 0} {
+	} else if {[string cmp $argv(1) "dialog"] == 0} {
 		log "\[Remote-controlled dialog window]";
 		zenity --info \
 		       --title="Dialog Box"\
 		       --text="test"
 
 	#3:
-	} elsif {[string cmp $argv(1) "killsv"] == 0} {
+	} else if {[string cmp $argv(1) "killsv"] == 0} {
 		log "\[Exiting server]"
 		exit
 
 	#4:
-	} elsif {[string cmp $argv(1) "shutdn"] == 0} {
+	} else if {[string cmp $argv(1) "shutdn"] == 0} {
 		log "\[Shutting down]"
 		poweroff
 
 	#5:
-	} elsif {[string cmp $argv(1) "clrscr"] == 0} {
+	} else if {[string cmp $argv(1) "clrscr"] == 0} {
 		clear
 
 	#6:

examples/sieve.zrc

@@ -23,7 +23,7 @@ fn sieve {
 	for {set p = 2} {$p <= $n} {inc p} {
 		if {$prime($p)} {
 			set ANSI = {\e[0;31m}
-		} elsif {$p == 42} {
+		} else if {$p == 42} {
 			set ANSI = {\e[0;32m}
 		} else {
 			set ANSI = {\e[0m}

examples/speedtest.out

@@ -0,0 +1,26 @@
+
+Bash will always be faster:
+0.08user 0.08system 0:00.16elapsed 98%CPU (0avgtext+0avgdata 6788maxresident)k
+0inputs+0outputs (0major+1106minor)pagefaults 0swaps
+
+Fish is also fast, but uses more memory:
+0.12user 0.07system 0:00.20elapsed 98%CPU (0avgtext+0avgdata 17200maxresident)k
+0inputs+0outputs (0major+2663minor)pagefaults 0swaps
+
+Csh will use more CPU power:
+0.86user 1.10system 0:01.96elapsed 100%CPU (0avgtext+0avgdata 4036maxresident)k
+0inputs+0outputs (3major+333953minor)pagefaults 0swaps
+
+Zrc will also have lower memory consumption:
+6.70user 22.51system 0:29.60elapsed 98%CPU (0avgtext+0avgdata 4508maxresident)k
+0inputs+0outputs (9major+1381354minor)pagefaults 0swaps
+
+Rc is comparable to Zrc in terms of performance:
+8.60user 18.88system 0:27.75elapsed 99%CPU (0avgtext+0avgdata 2980maxresident)k
+0inputs+0outputs (0major+3829864minor)pagefaults 0swaps
+
+Powershell performs the worst:
+29.91user 46.83system 1:10.31elapsed 109%CPU (0avgtext+0avgdata 124964maxresident)k
+0inputs+296outputs (0major+745159minor)pagefaults 0swaps
+
+CONCLUSION: Zrc doesn't totally suck ;) It's just very lightweight

examples/speedtest.zrc

@@ -0,0 +1,64 @@
+#!/usr/lib/zrc/bin/zrc
+set env(tf) = `{mktemp}
+set outfile = "speedtest.out"
+
+rm -f $outfile && unbuffer -p zrc -c {
+	fn main {
+		echo "\nBash will always be faster:"
+		time bash -c {
+			for i in {1..10000}; do
+				# Print out to the file
+				printf '%d ' $i >> $tf
+			done
+			rm $tf
+		}
+
+		echo "\nFish is also fast, but uses more memory:"
+		time fish -c {
+			for i in (seq 0 10000)
+				printf '%d ' $i >> $tf
+			end
+			rm $tf
+		}
+
+		echo "\nCsh will use more CPU power:"
+		time csh <<< {
+			@ i = 0
+			while ($i <= 10000)
+				# Just a comment... test
+				printf '%d ' $i >> $tf
+				@ i += 5
+			end
+			rm $tf
+		}
+
+		echo "\nZrc will also have lower memory consumption:"
+		time zrc -c {
+			for {set i = 0} {$i <= 10000} {inc i} {
+				# This is a comment
+				printf '%d ' $i >> $env(tf)
+			}
+			rm $env(tf)
+		}
+
+		echo "\nRc is comparable to Zrc in terms of performance:"
+		time rc -c {
+			for (i in `{seq 0 10000}) {
+				# Rc has an AST, so comments don't affect performance
+				printf '%d ' $i >> $tf
+			}
+			rm $tf
+		}
+
+		echo "\nPowershell performs the worst:"
+		time >(1=) pwsh -c {
+			for ($i = 0; $i -lt 10000; ++$i) {
+				# Comment test
+				printf '%d ' $i >> $env:tf
+			}
+			rm $env:tf
+		}
+
+		echo "\nCONCLUSION: Zrc doesn't totally suck ;) It's just very lightweight"
+	}; main >(2=1)
+} | tee $outfile

src/dispatch.hpp

@@ -132,25 +132,19 @@ Command(expr) {
 
 /** Executes a block if an expression evaluates non-zero **/
 Command(if) {
+	constexpr char se[] = "<expr> <block> [else < <arg1> <arg2>... >|<block>]";	
 	if (argc < 3)
-		syntax_error("<expr> <block> [elsif <expr> <block>...|else <block>]");
+		syntax_error(se);
 
 	if (OK(argv[1])) {
 		eval(argv[2]);
-	} else for (int i = 3; i < argc; i += 2) {
-		if (!strcmp(argv[i], "else")) {
-			if (i == argc-2)
-				eval(argv[i+1]);
-			else
-				syntax_error("else");
-			break;
-		}
-		if (!strcmp(argv[i], "elsif")) {
-			if (i <= argc-2 && OK(argv[++i])) {
-				eval(argv[i+1]);
-				break;
-			}
-		}
+	} else if (argc > 3 && !strcmp(argv[3], "else")) {
+		if (argc == 4)
+			syntax_error(se);
+		if (argc == 5)
+			eval(argv[4]);
+		else
+			exec(argc-4, argv+4);
 	}
 	NoReturn;
 }

src/exec.hpp

@@ -138,8 +138,10 @@ exec(int argc, char *argv[])
 	for (auto const& it : baks)
 		dup2(it.first, it.second);
 	baks.clear();
-	for (i = 0; i < argc; ++i)
+	for (i = 0; i < argc; ++i) {
 		free(argv[i]);
+		argv[i] = NULL;
+	}
 	make_new_jobs = false;
 
 	// set fg group ID

stdlib/list.zrc

@@ -144,7 +144,7 @@ fn lappend {
 		echo >(1=2) 'Expected 2 args!'
 		return {}
 	} else {
-		return [list {*}$argv(1) $argv(2)]
+		return [list {*}[subst $argv(1)] $argv(2)]
 	}
 }