Added "replace" tool.

tools/replace.nom

@@ -0,0 +1,144 @@
+#!/usr/bin/env nomsu -V6.13.12.8
+#
+    This is a tool to replace syntax trees with something new.
+    
+    Usage:
+        nomsu -t replace [-i] [--literal="$v1 $v2..."] <pattern> <replacement> file1 file2...
+    
+    Example:
+        nomsu -t replace "($1 and $2) and $3" "all of [$1, $2, $3]" my_file.nom
+    
+    If the "-i" flag is used, the file(s) will be edited in-place.
+    When editing in-place, if the "-f" flag is not used, each change will be
+        run past the user first.
+    If no files are passed in, this will read from stdin.
+    
+use "lib/os.nom"
+use "lib/consolecolor.nom"
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+if ((#$(COMMAND LINE ARGS).extras) < 2):
+    barf ("
+        Usage: nomsu -t replace [--literal="$v1 $v2..."] <pattern> <replacement> file1 file2...
+    ")
+$pattern = $(COMMAND LINE ARGS).extras.1
+$replacement = $(COMMAND LINE ARGS).extras.2
+$pattern_tree = ($pattern parsed)
+$replacement_tree = ($replacement parsed)
+$literal_vars = {}
+if $(COMMAND LINE ARGS).literal:
+    for $var in ($(COMMAND LINE ARGS).literal, all matches of "$([^ ]*)"):
+        $literal_vars.$var = (yes)
+
+if (($pattern_tree.type == "Var") and (not $literal_vars.($pattern_tree.1))):
+    barf "Pattern matches every part of the file."
+
+$pattern_vars = {
+    : for $ in recursive $pattern_tree:
+        if (($.type == "Var") and (not $literal_vars.($.1))): add $.1
+        for $child in $:
+            if ($child is a "Syntax Tree"):
+                recurse $ on $child
+}
+
+($tree matches $patt with $substitution_values) means:
+    # TODO: optimize
+    $substitution_values = {: for $k = $v in $substitution_values: add $k = $v}
+    when:
+        (not ($tree is syntax tree)): return (no)
+        (($patt.type == "Var") and $pattern_vars.($patt.1)):
+            if $substitution_values.($patt.1):
+                if ($tree == $substitution_values.($patt.1)):
+                    return $substitution_values
+                ..else:
+                    return (nil)
+            ..else:
+                $substitution_values.($patt.1) = $tree
+                return $substitution_values
+        ($tree.type != $patt.type): return (nil)
+        ($tree.type == "Action"):
+            if (($tree, get stub) != ($patt, get stub)): return (nil)
+    
+    for $ in 1 to (#$patt):
+        if ($patt.$ is syntax tree):
+            $new_values = ($tree.$ matches $patt.$ with $substitution_values)
+            unless $new_values:
+                return (nil)
+            
+            for $k = $v in $new_values:
+                $substitution_values.$k = $v
+        ..else:
+            unless ($tree.$ == $patt.$): return (nil)
+    
+    if ((#$tree) != (#$patt)): return (nil)
+    return $substitution_values
+
+$filenames = ($(COMMAND LINE ARGS).extras, from 3 to -1)
+if ((#$filenames) == 0):
+    say ("
+        Warning: searching stdin (ctrl-d to abort). To avoid this message, use nomsu -t find -
+    ")
+    $filenames = ["stdin"]
+
+for $filename in $filenames:
+    $file = (read file $filename)
+    unless $file:
+        barf "File does not exist: \$filename"
+    $code = (NomsuCode from ($Source $filename 1 (size of $file)) $file)
+    try:
+        $tree = ($code parsed)
+    ..and if it barfs $msg:
+        say
+            red ("
+                \$filename failed to parse:
+                \$msg
+            ")
+        $tree = (nil)
+    
+    unless $tree:
+        do next $filename
+    
+    $replaced = {}
+    $matched = {}
+    $user_answers = {}
+    ($tree with replacements) means
+        $tree, map
+            for $t:
+                $values = ($t matches $pattern_tree with {})
+                if $values:
+                    $matched.$t = (yes)
+                    for $k = $v in $values:
+                        $values.$k = ($v with replacements)
+                    $ret = ($replacement_tree with vars $values)
+                    if ($(COMMAND LINE ARGS).i and (not $(COMMAND LINE ARGS).f)):
+                        if ($user_answers.$t == (nil)):
+                            if ((#$user_answers) > 0): say ""
+                            $user_answers.$t = "n"
+                            say "\(bright)Should this:"
+                            say ("
+                                    \(bright)\(yellow)\("\(($t with replacements) as nomsu)", with "\n" -> "\n    ")\
+                                ..\(reset color)
+                            ")
+                            say "\(bright)..be replaced with:"
+                            
+                            say ("
+                                    \(bright)\(blue)\("\($ret as nomsu)", with "\n" -> "\n    ")\(reset color)
+                            ")
+                            
+                            $user_answers.$t = (ask "\(bright)..? [Y/n]\(reset color) ")
+                        
+                        if ($user_answers.$t == "n"): return (nil)
+                    $replaced.$t = (yes)
+                    return $ret
+    $tree2 = ($tree with replacements)
+    if $(COMMAND LINE ARGS).i:
+        if ((#$user_answers) > 0): say ""
+        say ("
+            \(#$replaced)/\(#$matched) replacement\("" if ((#$replaced) == 1) else "s") in \$filename
+        ")
+        
+        if ((#$replaced) > 0):
+            write "\($tree2 as nomsu)" to file $filename
+    ..else:
+        say ($tree2 as nomsu)