Added _dateStr intrinsic for basic date->string conversion.

Still need _dateVal, to go the other way (and to update makefiles).

MiniScript-cpp/src/DateTimeUtils.cpp

@@ -0,0 +1,185 @@
+//
+//  DateTimeUtils.cpp
+//  MiniScript
+//
+//  Created by Joe Strout on 2/1/23.
+//  Copyright © 2023 Joe Strout. All rights reserved.
+//
+
+#include "DateTimeUtils.h"
+#include "SplitJoin.h"
+#include <time.h>
+#include <math.h>
+
+namespace  MiniScript {
+
+static bool Match(const String s, size_t *posB, const String match) {
+	size_t matchLenB = match.LengthB();
+	if (s.SubstringB(*posB, matchLenB) == match) {
+		*posB += matchLenB;
+		return true;
+	}
+	return false;
+}
+
+String FormatDate(time_t t, const String formatSpec) {
+	tm dateTime;
+	localtime_r(&t, &dateTime);
+
+	const int BUFSIZE = 128;
+	char buffer[BUFSIZE];
+	setlocale(LC_ALL, "");
+
+	StringList result;
+	size_t posB = 0, lenB = formatSpec.LengthB();
+	while (posB < lenB) {
+		if (Match(formatSpec, &posB, "yyyy")) {			// year
+			result.Add(String::Format(dateTime.tm_year + 1900, "%04d"));
+		} else if (Match(formatSpec, &posB, "yyy")) {
+			result.Add(String::Format(dateTime.tm_year + 1900, "%03d"));
+		} else if (Match(formatSpec, &posB, "yy")) {
+			result.Add(String::Format(dateTime.tm_year % 100, "%02d"));
+		} else if (Match(formatSpec, &posB, "MMMM")) {	// month name
+			strftime(buffer, BUFSIZE, "%B", &dateTime);
+			result.Add(buffer);
+		} else if (Match(formatSpec, &posB, "MMM")) {	// month abbreviation
+			strftime(buffer, BUFSIZE, "%b", &dateTime);
+			result.Add(buffer);
+		} else if (Match(formatSpec, &posB, "MM")) {	// month number
+			result.Add(String::Format(dateTime.tm_mon + 1, "%02d"));
+		} else if (Match(formatSpec, &posB, "M")) {
+			result.Add(String::Format(dateTime.tm_mon + 1, "%d"));
+		} else if (Match(formatSpec, &posB, "dddd")) {	// weekday name
+			strftime(buffer, BUFSIZE, "%A", &dateTime);
+			result.Add(buffer);
+		} else if (Match(formatSpec, &posB, "ddd")) {	// weekday abbreviation
+			strftime(buffer, BUFSIZE, "%a", &dateTime);
+			result.Add(buffer);
+		} else if (Match(formatSpec, &posB, "dd")) {	// day (number)
+			result.Add(String::Format(dateTime.tm_mday, "%02d"));
+		} else if (Match(formatSpec, &posB, "d")) {
+			result.Add(String::Format(dateTime.tm_mday, "%d"));
+		} else if (Match(formatSpec, &posB, "hh")) {	// 12-hour hour
+			int twelveHourHour = (dateTime.tm_hour == 0 ? 12 : (dateTime.tm_hour - 1) % 12+1);
+			result.Add(String::Format(twelveHourHour, "%02d"));
+		} else if (Match(formatSpec, &posB, "h")) {
+			int twelveHourHour = (dateTime.tm_hour == 0 ? 12 : (dateTime.tm_hour - 1) % 12+1);
+			result.Add(String::Format(twelveHourHour, "%d"));
+		} else if (Match(formatSpec, &posB, "HH")) {	// 24-hour hour
+			result.Add(String::Format(dateTime.tm_hour, "%02d"));
+		} else if (Match(formatSpec, &posB, "H")) {
+			result.Add(String::Format(dateTime.tm_hour, "%d"));
+		} else if (Match(formatSpec, &posB, "mm")) {	// minute
+			result.Add(String::Format(dateTime.tm_min, "%02d"));
+		} else if (Match(formatSpec, &posB, "m")) {
+			result.Add(String::Format(dateTime.tm_min, "%d"));
+		} else if (Match(formatSpec, &posB, "ss")) {	// second
+			result.Add(String::Format(dateTime.tm_sec, "%02d"));
+		} else if (Match(formatSpec, &posB, "s")) {
+			result.Add(String::Format(dateTime.tm_sec, "%d"));
+		} else if (Match(formatSpec, &posB, "ffffff")) {	// fractional part of seconds value
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.6f", d);
+			result.Add(&buffer[2]);	// (skipping past "0.")
+		} else if (Match(formatSpec, &posB, "fffff")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.5f", d);
+			result.Add(&buffer[2]);	// (skipping past "0.")
+		} else if (Match(formatSpec, &posB, "ffff")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.4f", d);
+			result.Add(&buffer[2]);	// (skipping past "0.")
+		} else if (Match(formatSpec, &posB, "fff")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.3f", d);
+			result.Add(&buffer[2]);	// (skipping past "0.")
+		} else if (Match(formatSpec, &posB, "ff")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.2f", d);
+			result.Add(&buffer[2]);	// (skipping past "0.")
+		} else if (Match(formatSpec, &posB, "f")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.1f", d);
+			result.Add(&buffer[2]);	// (skipping past "0.")
+		} else if (Match(formatSpec, &posB, "FFFFFF")) {	// fractional part of seconds value, if nonzero
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.6f", d);
+			String s(&buffer[2]);	// (skipping past "0.")
+			if (s != "000000") result.Add(s);
+		} else if (Match(formatSpec, &posB, "FFFFF")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.5f", d);
+			String s(&buffer[2]);	// (skipping past "0.")
+			if (s != "00000") result.Add(s);
+		} else if (Match(formatSpec, &posB, "FFFF")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.4f", d);
+			String s(&buffer[2]);	// (skipping past "0.")
+			if (s != "0000") result.Add(s);
+		} else if (Match(formatSpec, &posB, "FFF")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.3f", d);
+			String s(&buffer[2]);	// (skipping past "0.")
+			if (s != "000") result.Add(s);
+		} else if (Match(formatSpec, &posB, "FF")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.2f", d);
+			String s(&buffer[2]);	// (skipping past "0.")
+			if (s != "00") result.Add(s);
+		} else if (Match(formatSpec, &posB, "F")) {
+			double d, i;
+			d = modf(t, &i);
+			snprintf(buffer, BUFSIZE, "%.1f", d);
+			String s(&buffer[2]);	// (skipping past "0.")
+			if (s != "0") result.Add(s);
+		} else if (Match(formatSpec, &posB, "tt")) {	// AM/PM
+			strftime(buffer, BUFSIZE, "%p", &dateTime);
+			result.Add(buffer);
+		} else if (Match(formatSpec, &posB, "t")) {
+			strftime(buffer, BUFSIZE, "%p", &dateTime);
+			buffer[1] = 0;	// (truncate to length 1)
+			result.Add(buffer);
+		} else if (Match(formatSpec, &posB, "gg") || Match(formatSpec, &posB, "g")) {
+			if (dateTime.tm_year + 1900 > 0) result.Add("A.D.");
+			else result.Add("B.C.");
+		} else if (Match(formatSpec, &posB, ":")) {
+			// Ugh.  Getting these in C is hard.  For now we're going to punt.
+			result.Add(":");
+		} else if (Match(formatSpec, &posB, "/")) {
+			// See comment above.
+			result.Add("/");
+		} else if (formatSpec[posB] == '"') {
+			// Find the closing quote, and output the contained string literal
+			size_t endPosB = posB + 1;
+			while (endPosB < lenB) {
+				char c = formatSpec[endPosB];
+				if (c == '\\') endPosB++;
+				else if (c == '"') break;
+			}
+			result.Add(formatSpec.Substring(posB + 1, endPosB - endPosB - 1));
+			posB = endPosB + 1;
+		} else if (Match(formatSpec, &posB, "\\") && posB < lenB) {
+			result.Add(formatSpec[posB++]);
+		} else {
+			result.Add(formatSpec.SubstringB(posB, 1));
+			posB++;
+		}
+	}
+
+	return Join("", result);
+}
+
+
+}
+

MiniScript-cpp/src/DateTimeUtils.h

@@ -0,0 +1,26 @@
+//
+//  DateTimeUtils.hpp
+//  MiniScript
+//
+//  Created by Joe Strout on 2/1/23.
+//  Copyright © 2023 Joe Strout. All rights reserved.
+//
+
+#ifndef DateTimeUtils_hpp
+#define DateTimeUtils_hpp
+
+#include <stdio.h>
+#include <time.h>
+#include "SimpleString.h"
+
+namespace MiniScript {
+
+String FormatDate(time_t dateTime, const String formatSpec);
+
+inline String FormatDate(time_t dateTime) {
+	return FormatDate(dateTime, "yyyy-MM-dd HH:mm:ss");
+}
+
+}
+
+#endif /* DateTimeUtils_hpp */

MiniScript-cpp/src/ShellIntrinsics.cpp

@@ -20,15 +20,16 @@
 #include "OstreamSupport.h"
 #include "MiniScript/SplitJoin.h"
 #include "whereami.h"
+#include "DateTimeUtils.h"
 
 #include <stdio.h>
+#include <time.h>
 #if _WIN32 || _WIN64
 	#define WINDOWS 1
 	#include <windows.h>
 	#include <Shlwapi.h>
 	#include <Fileapi.h>
 	#include <direct.h>
-	#include <time.h>
 	#define getcwd _getcwd
 	#define setenv _setenv
 #else
@@ -317,6 +318,39 @@ static IntrinsicResult intrinsic_exists(Context *context, IntrinsicResult partia
 	return IntrinsicResult(Value::Truth(found));
 }
 
+static double dateTimeEpoch() {
+	static double _result = 0;
+	if (_result == 0) {
+		tm baseDate;
+		memset(&baseDate, 0, sizeof(tm));
+		baseDate.tm_year = 2000 - 1900;	// (because tm_year is years since 1900!)
+		baseDate.tm_mon = 0;
+		baseDate.tm_mday = 1;
+		_result = mktime(&baseDate);
+	}
+	return _result;
+}
+
+static IntrinsicResult intrinsic_dateStr(Context *context, IntrinsicResult partialResult) {
+	Value date = context->GetVar("date");
+	Value format = context->GetVar("format");
+	String formatStr;
+	if (format.IsNull()) formatStr = "yyyy-MM-dd HH:mm:ss";
+	else formatStr = format.ToString();
+	double d;
+	if (date.IsNull()) {
+		time_t t;
+		time(&t);
+		d = t;
+	} else if (date.type == ValueType::Number) {
+		d = date.DoubleValue() + dateTimeEpoch();
+	} else {
+		// ToDo: parse a date string
+		d = 0;
+	}
+	return IntrinsicResult(FormatDate((time_t)d, formatStr));
+}
+
 static String timestampToString(const struct tm& t) {
 	String result = String::Format(1900 + t.tm_year) + "-";
 	if (t.tm_mon < 10) result += "0";
@@ -858,6 +892,11 @@ void AddShellIntrinsics() {
 	f = Intrinsic::Create("file");
 	f->code = &intrinsic_File;
 
+	f = Intrinsic::Create("_dateStr");
+	f->AddParam("date");
+	f->AddParam("format", "yyyy-MM-dd HH:mm:ss");
+	f->code = &intrinsic_dateStr;
+
 	i_getcwd = Intrinsic::Create("");
 	i_getcwd->code = &intrinsic_getcwd;
 
@@ -948,4 +987,5 @@ void AddShellIntrinsics() {
 	i_writeLines->AddParam("path");
 	i_writeLines->AddParam("lines");
 	i_writeLines->code = &intrinsic_writeLines;
+
 }

MiniScript-cpp/src/main.cpp

@@ -19,6 +19,7 @@
 #include "OstreamSupport.h"
 #include "MiniScript/SplitJoin.h"
 #include "ShellIntrinsics.h"
+#include "DateTimeUtils.h"	// TEMP for initial testing
 
 using namespace MiniScript;
 
@@ -277,6 +278,11 @@ int main(int argc, const char * argv[]) {
 	AddScriptPathVar("");
 	AddShellIntrinsics();
 
+	// HACK for initial testing:
+	time_t t;
+	time(&t);
+	Print(FormatDate(t, "MMM d, yyyy \\h hh:mm:ss.FF t"));
+
 	for (int i=1; i<argc; i++) {
 		String arg = argv[i];
 		if (arg == "-h" or arg == "-?" or arg == "--help") {