diff --git a/vlib/builtin/builtin.v b/vlib/builtin/builtin.v
index cbf2161a26..1e48fb8053 100644
--- a/vlib/builtin/builtin.v
+++ b/vlib/builtin/builtin.v
@@ -4,8 +4,8 @@
 module builtin
 
 __global (
-	g_m2_buf byteptr
-	g_m2_ptr byteptr
+	g_m2_buf byteptr 
+	g_m2_ptr byteptr 
 )
 
 // isnil returns true if an object is nil (only for C objects).
@@ -38,19 +38,19 @@ __global (
 	total_m              = i64(0)
 	nr_mallocs           = int(0)
 	// will be filled in cgen
-	as_cast_type_indexes   []VCastTypeIndexName
+	as_cast_type_indexes   []VCastTypeIndexName 
 )
 
 fn __as_cast(obj voidptr, obj_type int, expected_type int) voidptr {
 	if obj_type != expected_type {
-		mut obj_name := as_cast_type_indexes[0].tname
-		mut expected_name := as_cast_type_indexes[0].tname
+		mut obj_name := as_cast_type_indexes[0].tname.clone()
+		mut expected_name := as_cast_type_indexes[0].tname.clone()
 		for x in as_cast_type_indexes {
 			if x.tindex == obj_type {
-				obj_name = x.tname
+				obj_name = x.tname.clone()
 			}
 			if x.tindex == expected_type {
-				expected_name = x.tname
+				expected_name = x.tname.clone()
 			}
 		}
 		panic('as cast: cannot cast `$obj_name` to `$expected_name`')
diff --git a/vlib/v/ast/str.v b/vlib/v/ast/str.v
index e02e7a7173..ea2ce114f0 100644
--- a/vlib/v/ast/str.v
+++ b/vlib/v/ast/str.v
@@ -408,9 +408,7 @@ pub fn (node Stmt) str() string {
 			return node.str()
 		}
 		ConstDecl {
-			fields := node.fields.map(fn (f ConstField) string {
-				return '${f.name.trim_prefix(f.mod + '.')} = $f.expr'
-			})
+			fields := node.fields.map(field_to_string)
 			return 'const (${fields.join(' ')})'
 		}
 		ExprStmt {
@@ -441,6 +439,10 @@ pub fn (node Stmt) str() string {
 	}
 }
 
+fn field_to_string(f ConstField) string {
+	return '${f.name.trim_prefix(f.mod + '.')} = $f.expr'
+}
+
 pub fn (e CompForKind) str() string {
 	match e {
 		.methods { return 'methods' }
diff --git a/vlib/v/builder/builder.v b/vlib/v/builder/builder.v
index ff45f5313d..dd57b85e6e 100644
--- a/vlib/v/builder/builder.v
+++ b/vlib/v/builder/builder.v
@@ -285,7 +285,9 @@ pub fn (b &Builder) find_module_path(mod string, fpath string) ?string {
 
 fn (b &Builder) show_total_warns_and_errors_stats() {
 	if b.pref.is_stats {
-		println('checker summary: ${util.bold(b.checker.nr_errors.str())} V errors, ${util.bold(b.checker.nr_warnings.str())} V warnings')
+		estring := util.bold(b.checker.nr_errors.str())
+		wstring := util.bold(b.checker.nr_warnings.str())
+		println('checker summary: $estring V errors, $wstring V warnings')
 	}
 }
 
diff --git a/vlib/v/builder/c.v b/vlib/v/builder/c.v
index b0da21f188..77a51ff6fa 100644
--- a/vlib/v/builder/c.v
+++ b/vlib/v/builder/c.v
@@ -46,7 +46,9 @@ pub fn (mut b Builder) build_c(v_files []string, out_file string) {
 	f.writeln(output2) or { panic(err) }
 	f.close()
 	if b.pref.is_stats {
-		println('generated C source code size: ${util.bold((output2.count('\n') + 1).str())} lines, ${util.bold(output2.len.str())} bytes')
+		slines := util.bold((output2.count('\n') + 1).str())
+		sbytes := util.bold(output2.len.str())
+		println('generated C source code size: $slines lines, $sbytes bytes')
 	}
 	// os.write_file(out_file, b.gen_c(v_files))
 }
diff --git a/vlib/v/builder/compile.v b/vlib/v/builder/compile.v
index ea51093a7b..3de6555851 100644
--- a/vlib/v/builder/compile.v
+++ b/vlib/v/builder/compile.v
@@ -15,8 +15,8 @@ fn (mut b Builder) get_vtmp_filename(base_file_name string, postfix string) stri
 	if !b.pref.reuse_tmpc {
 		uniq = '.$rand.u64()'
 	}
-	return os.real_path(os.join_path(vtmp, os.file_name(os.real_path(base_file_name)) +
-		'$uniq$postfix'))
+	fname := os.file_name(os.real_path(base_file_name)) + '$uniq$postfix'
+	return os.real_path(os.join_path(vtmp, fname))
 }
 
 pub fn compile(command string, pref &pref.Preferences) {
@@ -45,7 +45,8 @@ pub fn compile(command string, pref &pref.Preferences) {
 		.x64 { b.compile_x64() }
 	}
 	if pref.is_stats {
-		println('compilation took: ${util.bold(sw.elapsed().milliseconds().str())} ms')
+		compilation_time := util.bold(sw.elapsed().milliseconds().str())
+		println('compilation took: $compilation_time ms')
 	}
 	b.exit_on_invalid_syntax()
 	// running does not require the parsers anymore
diff --git a/vlib/v/gen/c/assert.v b/vlib/v/gen/c/assert.v
index 8c4091821c..1979d0192c 100644
--- a/vlib/v/gen/c/assert.v
+++ b/vlib/v/gen/c/assert.v
@@ -58,12 +58,16 @@ fn (mut g Gen) gen_assert_metainfo(node ast.AssertStmt) string {
 	g.writeln('\t${metaname}.fpath = ${ctoslit(mod_path)};')
 	g.writeln('\t${metaname}.line_nr = $line_nr;')
 	g.writeln('\t${metaname}.fn_name = ${ctoslit(fn_name)};')
-	g.writeln('\t${metaname}.src = ${cnewlines(ctoslit(src))};')
+	metasrc := cnewlines(ctoslit(src))
+	g.writeln('\t${metaname}.src = $metasrc;')
 	match mut node.expr {
 		ast.InfixExpr {
-			g.writeln('\t${metaname}.op = ${ctoslit(node.expr.op.str())};')
-			g.writeln('\t${metaname}.llabel = ${cnewlines(ctoslit(node.expr.left.str()))};')
-			g.writeln('\t${metaname}.rlabel = ${cnewlines(ctoslit(node.expr.right.str()))};')
+			expr_op_str := ctoslit(node.expr.op.str())
+			expr_left_str := cnewlines(ctoslit(node.expr.left.str()))
+			expr_right_str := cnewlines(ctoslit(node.expr.right.str()))
+			g.writeln('\t${metaname}.op = $expr_op_str;')
+			g.writeln('\t${metaname}.llabel = $expr_left_str;')
+			g.writeln('\t${metaname}.rlabel = $expr_right_str;')
 			g.write('\t${metaname}.lvalue = ')
 			g.gen_assert_single_expr(node.expr.left, node.expr.left_type)
 			g.writeln(';')
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 43787c5160..64ff0bb599 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -737,10 +737,13 @@ pub fn (mut g Gen) write_typedef_types() {
 				if parent.info is table.Struct {
 					is_typedef = parent.info.is_typedef
 				}
-				parent_styp := if is_c_parent {
-					if !is_typedef { 'struct ' + parent.cname[3..] } else { parent.cname[3..] }
-				} else {
-					parent.cname
+				mut parent_styp := parent.cname
+				if is_c_parent {
+					if !is_typedef {
+						parent_styp = 'struct ' + parent.cname[3..]
+					} else {
+						parent_styp = parent.cname[3..]
+					}
 				}
 				g.type_definitions.writeln('typedef $parent_styp $typ.cname;')
 			}
@@ -1375,8 +1378,9 @@ fn (mut g Gen) for_in_stmt(node ast.ForInStmt) {
 			g.writeln(';')
 		}
 		i := if node.key_var in ['', '_'] { g.new_tmp_var() } else { node.key_var }
-		op_field := if node.cond_type.is_ptr() { '->' } else { '.' } +
-			if node.cond_type.share() == .shared_t { 'val.' } else { '' }
+		field_accessor := if node.cond_type.is_ptr() { '->' } else { '.' }
+		share_accessor := if node.cond_type.share() == .shared_t { 'val.' } else { '' }
+		op_field := field_accessor + share_accessor
 		g.empty_line = true
 		g.writeln('for (int $i = 0; $i < $cond_var${op_field}len; ++$i) {')
 		if node.val_var != '_' {
@@ -3454,7 +3458,8 @@ fn (mut g Gen) infix_expr(node ast.InfixExpr) {
 		e := right_sym.kind !in [.voidptr, .int_literal, .int]
 		if node.op in [.plus, .minus, .mul, .div, .mod, .lt, .eq] && ((a && b && e) || c || d) {
 			// Overloaded operators
-			g.write(g.typ(if !d { left_type } else { (left_sym.info as table.Alias).parent_type }))
+			the_left_type := if !d { left_type } else { (left_sym.info as table.Alias).parent_type }
+			g.write(g.typ(the_left_type))
 			g.write('_')
 			g.write(util.replace_op(node.op.str()))
 			g.write('(')
@@ -3463,7 +3468,8 @@ fn (mut g Gen) infix_expr(node ast.InfixExpr) {
 			g.expr(node.right)
 			g.write(')')
 		} else if node.op in [.ne, .gt, .ge, .le] && ((a && b && e) || c || d) {
-			typ := g.typ(if !d { left_type } else { (left_sym.info as table.Alias).parent_type })
+			the_left_type := if !d { left_type } else { (left_sym.info as table.Alias).parent_type }
+			typ := g.typ(the_left_type)
 			if node.op == .gt {
 				g.write('$typ')
 			} else {
@@ -3987,7 +3993,11 @@ fn (mut g Gen) select_expr(node ast.SelectExpr) {
 	objs_array := g.new_tmp_var()
 	g.write('Array_voidptr $objs_array = new_array_from_c_array($n_channels, $n_channels, sizeof(voidptr), _MOV((voidptr[$n_channels]){')
 	for i in 0 .. n_channels {
-		g.write(if i > 0 { ', &' } else { '&' })
+		if i > 0 {
+			g.write(', &')
+		} else {
+			g.write('&')
+		}
 		if tmp_objs[i] == '' {
 			g.expr(objs[i])
 		} else {
@@ -5574,11 +5584,12 @@ fn (mut g Gen) go_stmt(node ast.GoStmt, joinable bool) string {
 		g.writeln('$arg_tmp_var->ret_ptr = malloc(sizeof($s_ret_typ));')
 	}
 	is_opt := node.call_expr.return_type.has_flag(.optional)
-	gohandle_name := if node.call_expr.return_type == table.void_type {
-		if is_opt { '__v_thread_Option_void' } else { '__v_thread' }
+	mut gohandle_name := ''
+	if node.call_expr.return_type == table.void_type {
+		gohandle_name = if is_opt { '__v_thread_Option_void' } else { '__v_thread' }
 	} else {
 		opt := if is_opt { 'Option_' } else { '' }
-		'__v_thread_$opt${g.table.get_type_symbol(g.unwrap_generic(node.call_expr.return_type)).cname}'
+		gohandle_name = '__v_thread_$opt${g.table.get_type_symbol(g.unwrap_generic(node.call_expr.return_type)).cname}'
 	}
 	if g.pref.os == .windows {
 		simple_handle := if joinable && node.call_expr.return_type != table.void_type {
diff --git a/vlib/v/gen/c/fn.v b/vlib/v/gen/c/fn.v
index 12ef826c0c..b6aa0e5d6b 100644
--- a/vlib/v/gen/c/fn.v
+++ b/vlib/v/gen/c/fn.v
@@ -127,7 +127,8 @@ fn (mut g Gen) gen_fn_decl(node ast.FnDecl, skip bool) {
 		for gen_types in g.table.fn_gen_types[node.name] {
 			if g.pref.is_verbose {
 				syms := gen_types.map(g.table.get_type_symbol(it))
-				println('gen fn `$node.name` for type `${syms.map(node.name).join(', ')}`')
+				the_type := syms.map(node.name).join(', ')
+				println('gen fn `$node.name` for type `$the_type`')
 			}
 			g.cur_generic_types = gen_types
 			g.gen_fn_decl(node, skip)
diff --git a/vlib/v/gen/c/sql.v b/vlib/v/gen/c/sql.v
index 7996bd7174..e1812db7a3 100644
--- a/vlib/v/gen/c/sql.v
+++ b/vlib/v/gen/c/sql.v
@@ -402,7 +402,8 @@ fn (mut g Gen) expr_to_sql(expr ast.Expr, typ SqlType) {
 			// true/false literals were added to Sqlite 3.23 (2018-04-02)
 			// but lots of apps/distros use older sqlite (e.g. Ubuntu 18.04 LTS )
 			g.inc_sql_i()
-			g.sql_bind_int(if expr.val { '1' } else { '0' }, typ)
+			eval := if expr.val { '1' } else { '0' }
+			g.sql_bind_int(eval, typ)
 		}
 		ast.Ident {
 			// `name == user_name` => `name == ?1`
diff --git a/vlib/v/gen/js/js.v b/vlib/v/gen/js/js.v
index 2dc1c0cf0a..76575975fa 100644
--- a/vlib/v/gen/js/js.v
+++ b/vlib/v/gen/js/js.v
@@ -690,8 +690,9 @@ fn (mut g JsGen) gen_assign_stmt(stmt ast.AssignStmt) {
 			} else {
 				g.write(' $op ')
 				// TODO: Multiple types??
-				should_cast := (g.table.type_kind(stmt.left_types.first()) in shallow_equatables)
-							&& (g.cast_stack.len <= 0 || stmt.left_types.first() != g.cast_stack.last())
+				should_cast := 
+					(g.table.type_kind(stmt.left_types.first()) in js.shallow_equatables)
+					&& (g.cast_stack.len <= 0 || stmt.left_types.first() != g.cast_stack.last())
 
 				if should_cast {
 					g.cast_stack << stmt.left_types.first()
@@ -929,26 +930,28 @@ fn (mut g JsGen) gen_for_in_stmt(it ast.ForInStmt) {
 			if it.kind == .string {
 				g.write('Array.from(')
 				g.expr(it.cond)
-				g.write('.str.split(\'\').entries(), ([$it.key_var, $val]) => [$it.key_var, ')
-				if g.ns.name == 'builtin' { g.write('new ') }
+				g.write(".str.split(\'\').entries(), ([$it.key_var, $val]) => [$it.key_var, ")
+				if g.ns.name == 'builtin' {
+					g.write('new ')
+				}
 				g.write('byte($val)])')
 			} else {
 				g.expr(it.cond)
 				g.write('.entries()')
 			}
-			
 		} else {
 			g.write('for (const $val of ')
 			g.expr(it.cond)
 			if it.kind == .string {
-				g.write('.str.split(\'\')')
+				g.write(".str.split('')")
 			}
 			// cast characters to bytes
 			if val !in ['', '_'] && it.kind == .string {
 				g.write('.map(c => ')
-				if g.ns.name == 'builtin' { g.write('new ') }
+				if g.ns.name == 'builtin' {
+					g.write('new ')
+				}
 				g.write('byte(c))')
-				
 			}
 		}
 		g.writeln(') {')
@@ -1089,7 +1092,11 @@ fn (mut g JsGen) gen_struct_decl(node ast.StructDecl) {
 		g.inc_indent()
 		g.write('return `$js_name {')
 		for i, field in node.fields {
-			g.write(if i == 0 { ' ' } else { ', ' })
+			if i == 0 {
+				g.write(' ')
+			} else {
+				g.write(', ')
+			}
 			match g.typ(field.typ).split('.').last() {
 				'string' { g.write('$field.name: "\${this["$field.name"].toString()}"') }
 				else { g.write('$field.name: \${this["$field.name"].toString()} ') }
@@ -1417,13 +1424,13 @@ fn (mut g JsGen) gen_infix_expr(it ast.InfixExpr) {
 		g.write(')')
 	} else if r_sym.kind in [.array, .map, .string] && it.op in [.key_in, .not_in] {
 		g.expr(it.right)
-		g.write(if r_sym.kind == .map {
-			'.has('
+		if r_sym.kind == .map {
+			g.write('.has(')
 		} else if r_sym.kind == .string {
-			'.str.includes('
+			g.write('.str.includes(')
 		} else {
-			'.includes('
-		})
+			g.write('.includes(')
+		}
 		g.expr(it.left)
 		if l_sym.kind == .string {
 			g.write('.str')
@@ -1443,7 +1450,7 @@ fn (mut g JsGen) gen_infix_expr(it ast.InfixExpr) {
 				needs_cast = g.cast_stack.last() != greater_typ
 			}
 		}
-		
+
 		if needs_cast {
 			if g.ns.name == 'builtin' {
 				g.write('new ')
diff --git a/vlib/v/gen/x64/gen.v b/vlib/v/gen/x64/gen.v
index 57ea40a2f0..0f6c27c6ba 100644
--- a/vlib/v/gen/x64/gen.v
+++ b/vlib/v/gen/x64/gen.v
@@ -284,7 +284,9 @@ fn (mut g Gen) println(comment string) {
 		if s.len == 1 {
 			print(term.blue('0'))
 		}
-		print(term.blue(g.buf[i].hex()) + ' ')
+		gbihex := g.buf[i].hex()
+		hexstr := term.blue(gbihex) + ' '
+		print(hexstr)
 	}
 	g.debug_pos = g.buf.len
 	print(' ' + comment)
diff --git a/vlib/v/parser/struct.v b/vlib/v/parser/struct.v
index 9d0c612868..73428ead4d 100644
--- a/vlib/v/parser/struct.v
+++ b/vlib/v/parser/struct.v
@@ -267,14 +267,16 @@ fn (mut p Parser) struct_decl() ast.StructDecl {
 					is_public: is_field_pub
 				}
 			}
+			is_pub_field := is_embed || is_field_pub
+			is_mut_field := is_embed || is_field_mut
 			// save embeds as table fields too, it will be used in generation phase
 			fields << table.Field{
 				name: field_name
 				typ: typ
 				default_expr: ast.ex2fe(default_expr)
 				has_default_expr: has_default_expr
-				is_pub: if is_embed { true } else { is_field_pub }
-				is_mut: if is_embed { true } else { is_field_mut }
+				is_pub: is_pub_field
+				is_mut: is_mut_field
 				is_global: is_field_global
 				attrs: p.attrs
 			}
diff --git a/vlib/v/pref/pref.v b/vlib/v/pref/pref.v
index 24d0f0ab6c..8e9ce09ffd 100644
--- a/vlib/v/pref/pref.v
+++ b/vlib/v/pref/pref.v
@@ -156,7 +156,7 @@ pub fn parse_args(known_external_commands []string, args []string) (&Preferences
 	// for i, arg in args {
 	for i := 0; i < args.len; i++ {
 		arg := args[i]
-		current_args := args[i..]
+		current_args := args[i..].clone()
 		match arg {
 			'-apk' {
 				res.is_apk = true
@@ -441,12 +441,12 @@ pub fn parse_args(known_external_commands []string, args []string) (&Preferences
 					command_pos = i
 					continue
 				}
-				if command !in ['', 'build-module'] {
+				if command != '' && command != 'build-module' {
 					// arguments for e.g. fmt should be checked elsewhere
 					continue
 				}
-				eprint('Unknown argument `$arg`')
-				eprintln(if command.len == 0 { '' } else { ' for command `$command`' })
+				extension := if command.len == 0 { '' } else { ' for command `$command`' }
+				eprintln('Unknown argument `$arg`$extension')
 				exit(1)
 			}
 		}
@@ -554,7 +554,10 @@ pub fn cc_from_string(cc_str string) CompilerType {
 		return .gcc
 	}
 	// TODO
-	cc := cc_str.replace('\\', '/').split('/').last().all_before('.')
+	normalized_cc := cc_str.replace('\\', '/')
+	normalized_cc_array := normalized_cc.split('/')
+	last_elem := normalized_cc_array.last()
+	cc := last_elem.all_before('.')
 	if '++' in cc {
 		return .cplusplus
 	}