Adds iteration 2, targeting the C language

.gitignore

@@ -1,2 +1,3 @@
 /it0-out0.diff
 /it1-out*
+/it2-out*

Makefile

@@ -1,17 +1,36 @@
 TEE :=
 
-run:
+GCC_FLAGS := -g -O0 -Wall
+
+run: it1 it2
+
+it0:
+	echo "Hand made"
+
+it1:
 	cat it1-in.lang0 | python3 it0-out.py $(if $(TEE),| tee,> ) it1-out0.py
 
 	cat it1-in.lang0 | python3 it1-out0.py $(if $(TEE),| tee,> ) it1-out1.py
 	diff it1-out0.py it1-out1.py > it1-out1.diff
 	cat it1-in.lang0 | python3 it1-out1.py $(if $(TEE),| tee,> ) it1-out2.py
 	diff it1-out1.py it1-out2.py > it1-out2.diff
-	cat it1-in.lang0 | python3 it1-out2.py $(if $(TEE),| tee,> ) it1-out3.py
-	diff it1-out2.py it1-out3.py > it1-out3.diff
+	cat it1-in.lang0 | python3 it1-out2.py $(if $(TEE),| tee,> ) it1-out.py
+	diff it1-out2.py it1-out.py > it1-out.diff
 
 	# See how much our hand written code differs from resulting code
 	-diff it0-out.py it1-out0.py > it0-out0.diff
 
+it2: it1
+	cat it2-in.lang0 | python3 it1-out.py $(if $(TEE),| tee,> ) it2-out0.py
+
+	cat it2-in.lang0 | python3 it2-out0.py $(if $(TEE),| tee,> ) it2-out1.c && gcc it2-out1.c -o it2-out1 $(GCC_FLAGS)
+#	diff it2-out0.c it2-out1.c > it2-out1.diff
+	cat it2-in.lang0 | ./it2-out1 $(if $(TEE),| tee,> ) it2-out2.c && gcc it2-out2.c -o it2-out2 $(GCC_FLAGS)
+	diff it2-out1.c it2-out2.c > it2-out2.diff
+	cat it2-in.lang0 | ./it2-out2 $(if $(TEE),| tee,> ) it2-out.c && gcc it2-out.c -o it2-out $(GCC_FLAGS)
+	diff it2-out2.c it2-out.c > it2-out.diff
+
 clean:
-	-rm it1-out*
+	-rm it1-out* it2-out*
+
+.PHONY: it2

it0-out.py

@@ -95,6 +95,11 @@ def parseexprcall():
 
     emit(')')
 
+def parsestatdeclare(indent):
+    skipchar(' ')
+    var = lexident()
+    skipchar(eol)
+
 def parsestatset(indent):
     skipchar(' ')
     var = lexident()
@@ -195,6 +200,10 @@ def parsestat(indent):
     call = lexident()
     trace('call', call)
 
+    if call == "declare":
+        parsestatdeclare(indent)
+        return
+
     if call == "set":
         parsestatset(indent)
         return
@@ -269,6 +278,7 @@ def parseblock(indent):
 
 def parsefunc():
     funcname = lexident()
+
     trace('funcname', funcname)
     emit('def ')
     emit(funcname)
@@ -283,6 +293,15 @@ def parsefunc():
         emit(var)
         first = False
 
+    if '/' == peek():
+        # Ahead declaration
+        skipchar('/')
+        skipchar(eol)
+        emit("):\n")
+        emit("    pass # ahead declaration\n")
+        emit("\n")
+        return
+
     skipchar(':')
     skipchar(eol)
 

it1-in.lang0

@@ -7,6 +7,7 @@ increaseindent indent:
 /
 
 lexident:
+	declare word
 	set word ""
 	forever
 		calc char peek
@@ -81,6 +82,12 @@ parseexprcall:
 	emit ")"
 /
 
+parsestatdeclare indent:
+	skipchar " "
+	calc var lexident
+	skipchar eol
+/
+
 parsestatset indent:
 	skipchar " "
 	calc var lexident
@@ -105,6 +112,8 @@ parsestatcalc indent:
 	skipchar eol
 /
 
+parseblock indent/
+
 parsestatif indent:
 	skipchar " "
 	emit indent
@@ -194,6 +203,11 @@ parsestatskipchar indent:
 parsestat indent:
 	calc call lexident
 	trace call
+	calc isset eq call "declare"
+	if isset
+		parsestatdeclare indent
+		return
+	/
 	calc isset eq call "set"
 	if isset
 		parsestatset indent
@@ -305,6 +319,11 @@ parseblock indent:
 
 parsefunc:
 	calc funcname lexident
+	calc char peek
+	calc iseoblock eq char "/"
+	if iseoblock
+		return
+	/
 	trace funcname
 	emit "def "
 	emit funcname
@@ -327,6 +346,16 @@ parsefunc:
 		emit var
 		set first "0"
 	/
+	calc char peek
+	calc iseoblock eq char "/"
+	if iseoblock
+		skipchar "/"
+		skipchar eol
+		emit "):\n"
+		emit "    pass # ahead declaration\n"
+		emit "\n"
+		return
+	/
 	skipchar ":"
 	skipchar eol
 	emit "):\n"

it2-in.lang0

@@ -0,0 +1,584 @@
+increaseindent indent:
+	calc indent addstringchar indent " "
+	calc indent addstringchar indent " "
+	calc indent addstringchar indent " "
+	calc indent addstringchar indent " "
+	return indent
+/
+
+lexident:
+	declare char
+	declare isbeforea
+	declare isafterz
+	declare word
+	set word ""
+	forever
+		calc char peek
+		calc isbeforea lt char "a"
+		if isbeforea
+			break
+		/
+		calc isafterz lt "z" char
+		if isafterz
+			break
+		/
+		calc word addstringchar word char
+		skip
+	/
+	return word
+/
+
+parseconststring:
+	declare char
+	declare iseof
+	declare isquote
+	skipchar quote
+	emit quote
+	forever
+		calc char peek
+		calc iseof eq char eof
+		if iseof
+			break
+		/
+		calc isquote eq char quote
+		if isquote
+			break
+		/
+		emit char
+		skip
+	/
+	skipchar quote
+	emit quote
+	return
+/
+
+parseexprvarref:
+	declare varname
+	calc varname lexident
+	emit "var_"
+	emit varname
+	return
+/
+
+parseexprcall:
+	declare char
+	declare first
+	declare funcname
+	declare isspace
+	declare isnotspace
+	declare isfirst
+	declare isnotfirst
+	declare isquote
+	declare isnotquote
+	calc funcname lexident
+	emit funcname
+	emit "("
+	set first "1"
+	forever
+		calc char peek
+		calc isspace eq char " "
+		calc isnotspace not isspace
+		if isnotspace
+			break
+		/
+		skip
+		calc isfirst eq first "1"
+		calc isnotfirst not isfirst
+		if isnotfirst
+			emit ", "
+		/
+		calc char peek
+		calc isquote eq char quote
+		calc isnotquote not isquote
+		if isquote
+			parseconststring
+		/
+		if isnotquote
+			parseexprvarref
+		/
+		set first "0"
+	/
+	emit ")"
+	return
+/
+
+parsestatdeclare indent:
+	declare var
+	skipchar " "
+	calc var lexident
+	emit indent
+	emit "char * var_"
+	emit var
+	emit ";"
+	emit eol
+	skipchar eol
+	return
+/
+
+parsestatset indent:
+	declare var
+	skipchar " "
+	calc var lexident
+	skipchar " "
+	emit indent
+	emit "var_"
+	emit var
+	emit " = "
+	parseconststring
+	emit ";"
+	emit eol
+	skipchar eol
+	return
+/
+
+parsestatcalc indent:
+	declare var
+	skipchar " "
+	calc var lexident
+	skipchar " "
+	emit indent
+	emit "var_"
+	emit var
+	emit " = "
+	parseexprcall
+	emit ";"
+	emit eol
+	skipchar eol
+	return
+/
+
+parseblock indent/
+
+parsestatif indent:
+	declare indentt
+	skipchar " "
+	emit indent
+	emit "if ( 0 < strlen("
+	parseexprvarref
+	emit ") )\n"
+	emit indent
+	emit "{\n"
+	skipchar eol
+	calc indentt increaseindent indent
+	parseblock indentt
+	emit indent
+	emit "}\n"
+	return
+/
+
+parsestatforever indent:
+	declare indentt
+	emit indent
+	emit "while (1)\n"
+	emit indent
+	emit "{\n"
+	skipchar eol
+	calc indentt increaseindent indent
+	parseblock indentt
+	emit indent
+	emit "}\n"
+	return
+/
+
+parsestatbreak indent:
+	emit indent
+	emit "break;\n"
+	skipchar eol
+	return
+/
+
+parsestatreturn indent:
+	declare char
+	declare isspace
+	declare isnotspace
+	emit indent
+	emit "return "
+	calc char peek
+	calc isspace eq char " "
+	calc isnotspace not isspace
+	if isspace
+		skip
+		parseexprvarref
+	/
+	if isnotspace
+		emit "0"
+	/
+	emit ";"
+	emit eol
+	skipchar eol
+	return
+/
+
+parsestatemit indent:
+	declare char
+	declare isquote
+	declare isnotquote
+	emit indent
+	emit "emit("
+	skipchar " "
+	calc char peek
+	calc isquote eq char quote
+	calc isnotquote not isquote
+	if isquote
+		parseconststring
+	/
+	if isnotquote
+		parseexprvarref
+	/
+	emit ");\n"
+	skipchar eol
+	return
+/
+
+parsestattrace indent:
+	declare varname
+	emit indent
+	emit "trace("
+	emit quote
+	skipchar " "
+	calc varname lexident
+	emit varname
+	emit quote
+	emit ", var_"
+	emit varname
+	emit ");\n"
+	skipchar eol
+	return
+/
+
+parsestatskipchar indent:
+	declare char
+	declare isquote
+	declare isnotquote
+	skipchar " "
+	emit indent
+	emit "skipchar("
+	calc char peek
+	calc isquote eq char quote
+	calc isnotquote not isquote
+	if isquote
+		parseconststring
+	/
+	if isnotquote
+		parseexprvarref
+	/
+	emit ");\n"
+	skipchar eol
+	return
+/
+
+parsestat indent:
+	declare call
+	declare char
+	declare first
+	declare iscall
+	declare isfirst
+	declare isspace
+	declare isquote
+	declare isnotfirst
+	declare isnotspace
+	declare isnotquote
+	calc call lexident
+	trace call
+	calc iscall eq call "declare"
+	if iscall
+		parsestatdeclare indent
+		return
+	/
+	calc iscall eq call "set"
+	if iscall
+		parsestatset indent
+		return
+	/
+	calc iscall eq call "calc"
+	if iscall
+		parsestatcalc indent
+		return
+	/
+	calc iscall eq call "if"
+	if iscall
+		parsestatif indent
+		return
+	/
+	calc iscall eq call "forever"
+	if iscall
+		parsestatforever indent
+		return
+	/
+	calc iscall eq call "break"
+	if iscall
+		parsestatbreak indent
+		return
+	/
+	calc iscall eq call "return"
+	if iscall
+		parsestatreturn indent
+		return
+	/
+	calc iscall eq call "emit"
+	if iscall
+		parsestatemit indent
+		return
+	/
+	calc iscall eq call "trace"
+	if iscall
+		parsestattrace indent
+		return
+	/
+	calc iscall eq call "skipchar"
+	if iscall
+		parsestatskipchar indent
+		return
+	/
+	emit indent
+	emit call
+	emit "("
+	set first "1"
+	forever
+		calc char peek
+		calc isspace eq char " "
+		calc isnotspace not isspace
+		if isnotspace
+			break
+		/
+		skip
+		calc char peek
+		calc isquote eq char quote
+		calc isnotquote not isquote
+		if isquote
+			parseconststring
+		/
+		if isnotquote
+			parseexprvarref
+		/
+		calc isfirst eq first "1"
+		calc isnotfirst not isfirst
+		if isnotfirst
+			emit ", "
+		/
+		set first "0"
+	/
+	skipchar eol
+	emit ");\n"
+	return
+/
+
+parseblock indent:
+	declare char
+	declare copy
+	declare iseol
+	declare isnoteol
+	declare isdone
+	declare iseoblock
+	forever
+		forever
+			calc char peek
+			calc iseol eq char eol
+			calc isnoteol not iseol
+			if isnoteol
+				break
+			/
+			skip
+		/
+		set copy "    "
+		forever
+			calc isdone eq copy indent
+			if isdone
+				break
+			/
+			skipchar "\t"
+			calc copy increaseindent copy
+		/
+		calc char peek
+		calc iseoblock eq char "/"
+		if iseoblock
+			skip
+			skipchar eol
+			break
+		/
+		skipchar "\t"
+		parsestat indent
+	/
+	return
+/
+
+parsefunc:
+	declare char
+	declare first
+	declare funcname
+	declare iseoblock
+	declare isfirst
+	declare isspace
+	declare isnotfirst
+	declare isnotspace
+	declare var
+	calc funcname lexident
+	trace funcname
+	emit "char * "
+	emit funcname
+	emit "("
+	set first "1"
+	forever
+		calc char peek
+		calc isspace eq char " "
+		calc isnotspace not isspace
+		if isnotspace
+			break
+		/
+		skip
+		calc var lexident
+		calc isfirst eq first "1"
+		calc isnotfirst not isfirst
+		if isnotfirst
+			emit ", "
+		/
+		emit "char * var_"
+		emit var
+		set first "0"
+	/
+	calc char peek
+	calc iseoblock eq char "/"
+	if iseoblock
+		skipchar "/"
+		skipchar eol
+		emit ");"
+		emit "\n"
+		return
+	/
+	skipchar ":"
+	skipchar eol
+	emit ")\n{\n"
+	parseblock "    "
+	emit "}\n\n"
+	return
+/
+
+emitheader:
+	emit "#include <assert.h>\n"
+	emit "#include <stdio.h>\n"
+	emit "#include <stdlib.h>\n"
+	emit "#include <string.h>\n"
+	emit eol
+	emit eol
+	emit "char var_eof[2] = {-1, 0};\n"
+	emit "char var_eol[2] = {10, 0};\n"
+	emit "char var_quote[2] = {34, 0};\n"
+	emit "char var_false[1] = {0};\n"
+	emit "char var_true[2] = {'1', 0};\n"
+	emit eol
+	emit eol
+	emit "char * eq(char * a, char * b)\n"
+	emit "{\n"
+	emit "    return (strcmp(a, b) == 0) ? var_true : var_false;\n"
+	emit "}\n"
+	emit "\n"
+	emit "char * lt(char * a, char * b)\n"
+	emit "{\n"
+	emit "    return (strcmp(a, b) < 0) ? var_true : var_false;\n"
+	emit "}\n"
+	emit "char * not(char * a)\n"
+	emit "{\n"
+	emit "    return (strcmp(a, var_true) != 0) ? var_true : var_false;\n"
+	emit "}\n"
+	emit "\n"
+	emit "char * addstringchar(char * str, char * chr)\n"
+	emit "{\n"
+	emit "    int str_len = strlen(str);\n"
+	emit "    assert(strlen(chr) == 1);\n"
+	emit "    char * res = malloc((str_len + 2) * sizeof(char));\n"
+	emit "    strcpy(res, str);\n"
+	emit "    res[str_len + 0] = chr[0];\n"
+	emit "    res[str_len + 1] = 0;\n"
+	emit "    return res;\n"
+	emit "}\n"
+	emit "\n"
+	emit "char * emit(char * str)\n"
+	emit "{\n"
+	emit "    fputs(str, stdout);\n"
+	emit "    return 0;\n"
+	emit "}\n"
+	emit "\n"
+	emit "char * trace(char * var_name, char * var_value)\n"
+	emit "{\n"
+	emit "    const char * env_trace = getenv("
+	emit quote
+	emit "TRACE"
+	emit quote
+	emit ");\n"
+	emit "    if( !env_trace ) return 0;\n"
+	emit "    fputs(var_name, stderr);\n"
+	emit "    fputs("
+	emit quote
+	emit "="
+	emit quote
+	emit ", stderr);\n"
+	emit "    fputs(var_value, stderr);\n"
+	emit "    fputs(var_eol, stderr);\n"
+	emit "    return 0;\n"
+	emit "}\n"
+	emit eol
+	emit "int LINE = 1;\n"
+	emit eol
+	emit "char * peek()\n"
+	emit "{\n"
+	emit "    char * res = malloc(2*sizeof(char));\n"
+	emit "    res[0] = getc(stdin);\n"
+	emit "    res[1] = 0;\n"
+	emit "    ungetc(res[0], stdin);\n"
+	emit "    return res;\n"
+	emit "}\n"
+	emit "\n"
+	emit "void skip()\n"
+	emit "{\n"
+	emit "    char c = getc(stdin);\n"
+	emit "    if( c == 10 ) LINE += 1;\n"
+	emit "}\n"
+	emit "\n"
+	emit "void skipchar(char * chr)\n"
+	emit "{\n"
+	emit "    assert(strlen(chr) == 1);\n"
+	emit "    char * act = peek();\n"
+	emit "    assert(strlen(act) == 1);\n"
+	emit "    if( chr[0] == act[0] ) {skip(); return;};\n"
+	emit "    fprintf(stderr, "
+	emit quote
+	emit "Expected '%c' on line %d but saw '%c' instead%c"
+	emit quote
+	emit ", chr[0], LINE, act[0], 10);\n"
+	emit "    exit(1);\n"
+	emit "}\n"
+	emit "\n"
+	return
+/
+
+emitfooter:
+	emit ""
+	return
+/
+
+main:
+	declare char
+	declare iseof
+	declare iseol
+	declare isnoteol
+	emitheader
+	forever
+		calc char peek
+		calc iseof eq char eof
+		if iseof
+			break
+		/
+		forever
+			calc char peek
+			calc iseol eq char eol
+			calc isnoteol not iseol
+			if isnoteol
+				break
+			/
+			skip
+		/
+		parsefunc
+	/
+	emitfooter
+	return
+/