Manual

From NEOSYS Dev Wiki
Jump to navigationJump to search

ICONV/OCONV PATTERNS

Decimal (MD/MC)

input conversion (string) output
1234 MD2 12.34
1234 MD20 1234.00
1234 MD20, 1,234.00
1234.5678 MD2 12.35
1234.5678 MD20 1234.57
1234.5678 MD20, 1,234.57
1234 MC2 12,34
1234 MC20 1234,00
1234 MC20, 1.234,00
1234 MD20- 1234.00

Date (D)

input conversion (string) output
12345 D 18 OCT 2001
12345 D/ 10/18/2001
12345 D- 10-18-2001
12345 D2 18 OCT 01
12345 D/E 18/10/2001
12345 DS 2001 OCT 18
12345 DS/ 2001/10/18
12345 DM 10
12345 DMA OCTOBER
12345 DY 2001
12345 DY2 01
12345 DD 18
12345 DW 4
12345 DWA THURSDAY
12345 DQ 4
12345 DJ 291
12345 DL 31

Time (MT)

input conversion (string) output
234800 MT 17:13
234800 MTH 05:13PM
234800 MTS 17:13:20
234800 MTHS 05:13:20PM
0 MT 00:00
0 MTH 12:00AM
0 MTS 00:00:00
0 MTHS 12:00:00AM

Hex (HEX/MX)

input conversion (string) output
ab HEX (same as HEX8 or HEX4 depending on platform)
ab HEX8 0000006100000062
ab HEX4 00610062
ab HEX2 6162
15 MX F
254 MX FE
255 MX FF
256 MX 100
27354234 MX 1A1647A

Text (L/R/T)

input conversion (string)output
abcd L#3 abc
ab L#3 ab␣
abcd R#3 bcd
ab R#3 ␣ab
ab T#3 ab␣
abcd T#3 abc™d␣␣
42 L(0)#5 42000
42 R(0)#5 00042
42 T(0)#5 42000

Dictionaries

Exodus dictionaries enable classic multivalue database data definition. Dictionaries are just normal Exodus multivalue files that contain one record for each data column definition. You can use Exodus's edir program to manually edit dictionaries.

Dictionary file names must start with the word "dict_". For example, if you have a "books" file, then you will probably have a "dict_books" file.

You can list the contents of a dictionary by typing "list dict_filename".

Exodus Dictionary Format

0 DICTID Field/Column Code
1 DICTTYPE "F" or "S" : "F" means use Field No (i.e. raw data) and "S" means use Source Code (i.e. a function).
2 FIELDNO Field number (0=key, 1=field 1 etc for "Fields"
3 TITLE Title on reports
4 SM S or M or Mnn : "Single Value" or "Multivalue" or "Multivalue Group nn"
5 KEYPARTNO Multipart keys are separated by * characters.
6
7 CONVERSION Conversion (MD/MT/D etc.)
8 SOURCE Source Code of a subroutine to calculate the field. Multivalues are lines and the result must be placed in a variable "ANS".
9 JUST "L" or "R" or "T" requesting left, right or text justification
10 WIDTH Column Width on fixed width reports

Sort/Select Command

Exodus provides the classic multivalue sort/select command within any Exodus program followed by readnext().

Classic multivalue select/readnext functions only provide the keys of the selected records. Exodus provides the classic select/readnext and also selectrecords/readnextrecord which provides complete records instead of just keys.

The format of the select/sselect command is as follows: 

 SELECT|SSELECT

 {max_number_of_records}

 {using filename}

 filename

 {datakeyvalue} ...

 {BY|BY-DSND fieldname} ...
 
 {

  WITH

  {NO|ALL|ANY}

  dict_field_id

  {
   CONTAINING|STARTING|ENDING|LIKE|EQ|NE|NOT|GT|LT|GE|LE=|<>|>|<|>=|<= value(s)
   |
   BETWEEN value AND value
  }

  {AND|OR}

 } ...

Functions and Commands

String Commands

Most string functions like trim() that return a new modified string have a corresponding modify in place command like function like trimmer() that is is usually much faster. So we have convert and converter, replace and replacer, insert and inserter and so on.

Therefore by preference use 

trimmer(v1);
// or
v1.trimmer()

instead of 

v1 = trim(v1);
// or
v1 = v1.trim();

Function Types

TYPE FUNCTION TYPE
var= traditional functions that return values and can be used in expressions and be on the right hand side of assignments
if traditional conditional statements that started with "if" or ended with "then/else" (or could have)
cmd traditional commands with no outputs
exp traditional commands that now have outputs and can be used in expressions

Parameters/Argument Types

in Parameters that provide data to the function. Can be variables or raw data like 1 or "X"
unspecified Same as "in". Omission of the most common type de-clutters the documentation. NB When defining your own subroutines and functions "in" cannot be omitted from the source code.
io Parameters that may provide and/or return data. Must be variables. Cannot be raw data like 1 or "X"
out Parameters that return data. Must be variables. Cannot be raw data like 1 or "X"

Optional Parameters

Key Default
="" ""
=" " " "
="." "."
=1 1
=0 0
=true true
=false false

Complete List of Functions

Generated by cli/gendoc from var.h at 29JAN2025 8:13PM

Math/Boolean
Usage Function Comment
var= num.abs() Absolute value 
var(-12.34).abs(); // 12.34
var= num.pwr(exponent) Power 
var(2).pwr(8); // 256
var= num.rnd() Pseudo random number generator 
var(100).rnd(); // 0 to 99 pseudo random
cmd num.initrnd() Initialise the seed for rnd() 
var(123).initrnd(); // Set seed to 123
var= num.exp() Power of e 
var(1).exp(); // 2.718281828459045
var= num.sqrt() Square root 
var(100).sqrt(); // 10
var= num.sin() Sine of degrees 
var(30).sin(); // 0.5
var= num.cos() Cosine of degrees 
var(60).cos(); // 0.5
var= num.tan() Tangent of degrees 
var(45).tan(); // 1
var= num.atan() Arctangent of degrees 
var(1).atan(); // 45
var= num.loge() Natural logarithm 
var(2.718281828459045).loge(); // 1
var= num.integer() Truncate decimal numbers towards zero. 
var(2.9).integer(); // 2
var(-2.9).integer(); // -2
var= num.floor() Truncate decimal numbers towards negative 
var(2.9).floor(); // 2
var(-2.9).floor(); // -3
var= num.round(ndecimals = 0) Round decimal numbers to a desired number of decimal places

.5 always rounds away from zero. 

var(0.455).round(2); // "0.46"
var(-0.455).round(2); // "-0.46"
var(1.455).round(2); // "1.46"
var(-1.455).round(2); // "-1.46"
var= num.mod(divisor)


Locale
Usage Function Comment
expr var.getxlocale() Gets the current thread's default locale codepage code 
var().getxlocale(); // e.g. "en_US.utf8"
getxlocale(); // ditto
if str.setxlocale() Sets the current thread's default locale codepage code
if (not "de_DE.utf8"_var.setxlocale()) ... // true if successful
if (setxlocale("de_DE.utf8")) ... // ditto


String Creation
Usage Function Comment
var= var.chr(num) Create a string of a single char (byte) given an integer 0-255.

0-127 -> ASCII, 128-255 -> invalid UTF-8 so cannot be written to database or used various exodus string operations 

var().chr(0x61); // "a"
chr(0x61); // ditto
var= var.textchr(num) Create a string of a single unicode code point in utf8 encoding.

To get utf codepoints > 2^63 you must provide negative ints
Not providing implicit constructor from var to unsigned int due to getting ambigious conversions
since int and unsigned int are parallel priority in c++ implicit conversions 

var().textchr(171416); // "𩶘" or "\xF0A9B698"
textchr(171416); // ditto
var= var.str(num) Create a string by repeating a given character or string 
"ab"_var.str(3); // "ababab"
str("ab"_var, 3); // ditto
var= num.space() Create string of space characters.
var(3).space(); // "␣␣␣"
space(3); // ditto
var= num.numberinwords(languagename_or_locale_id = "") Create a string describing a given number in words
var(123.45).numberinwords("de_DE");
//"ein­hundert­drei­und­zwanzig Komma vier fünf"


String Scanning
Usage Function Comment
var= str.seq() Returns the character number of the first char. 
"abc"_var.seq(); // 0x61 97
seq("abc"_var); // 0x61 97
var= str.textseq() Returns the Unicode character number of the first unicode code point. 
"Γ"_var.textseq(); // 915 U+0393: Greek Capital Letter Gamma (Unicode Character)
textseq("Γ"); // ditto
var= str.len() Returns the length of a string in number of chars 
"abc"_var.len(); // 3
len("abc"_var); // ditto
var= str.textwidth() Returns the number of output columns.

Allows multi column unicode and reduces combining characters etc. like e followed by grave accent
Possibly does not properly calculate combining sequences of graphemes e.g. face followed by colour 

"🤡x🤡"_var.textwidth(); // 5
textwidth("🤡x🤡"_var); // ditto
var= str.textlen() Returns the number of Unicode code points 
"Γιάννης"_var.textlen(); // 7
textlen("Γιάννης"_var); // ditto
var= str.fcount(sepstr) Returns the number of fields separated by sepstr present.

It is the same as var.count(sepstr) + 1 except that and empty string returns 0 

"a1**c3"_var.fcount("*"); // 3
fcount("a1**c3"_var, "*"); // ditto
var= str.count(sepstr) Return the number of sepstr found 
"a1*b2*c3"_var.count("*"); // 3
count("a1*b2*c3"_var, "*"); // ditto
if str.starts(prefix) Returns true if starts with prefix 
"abc"_var.starts("ab"); // true
if str.ends(suffix) Returns true if ends with suffix 
"abc"_var.ends("bc"); // true
if str.contains(substr) Returns true if starts, ends or contains substr 
"abcd"_var.contains("bc"); // true
var= str.index(substr, startchar1 = 1) Returns char no if found or 0 if not. startchar1 is byte no to start at. 
"abcd"_var.index("bc"); // 2
var= str.indexn(substr, occurrence) ditto. Occurrence 1 = find first occurrence 
"abcabc"_var.index("bc", 2); // 5
var= str.indexr(substr, startchar1 = -1) ditto. Reverse search.

startchar1 defaults to -1 meaning start searching from the last byte 

"abcabc"_var.indexr("bc"); // 5
var= str.match(regex, regex_options = "") Returns all results of regex matching

Multiple matches are in fields. Groups are in values 

"abc1abc2"_var.match("bc(\\d)"); // "bc1]1^bc2]2"

regex_options:

l - Literal (any regex chars are treated as normal chars)

i - Case insensitive

p - ECMAScript/Perl (the default)
b - Basic POSIX (same as sed)
e - Extended POSIX
a - awk
g - grep
eg - egrep or grep -E

char ranges like a-z are locale sensitive if ECMAScript

m - Multiline. Default in boost (and therefore exodus)
s - Single line. Default in std::regex

f - First only. Only for replace() (not match() or search())

w - Wildcard glob style (e.g. *.cfg) not regex style. Only for match() and search(). Not replace().

var= str.match(regex) Ditto
var= str.search(regex, io startchar1, regex_options = "") Search for first match of a regular expression starting at startchar1

Updates startchar1 ready to search for the next match
regex_options as for match() 

var startchar1 = 1;
"abc1abc2"_var.search("bc(\\d)", startchar1); // returns "bc1]1"
// startchar1 becomes 5 ready for the next search
var= str.search(regex) Ditto starting from first char
var= str.search(regex, io startchar1) Ditto given a rex
var= str.search(regex) Ditto starting from first char.


String Conversion - Chainable. Non-Mutating
Usage Function Comment
var= str.ucase() Upper case 
"Γιάννης"_var.ucase(); // "ΓΙΆΝΝΗΣ"
var= str.lcase() Lower case 
"ΓΙΆΝΝΗΣ"_var.lcase(); // "γιάννης"
var= str.tcase() Title case (first letters) 
"γιάννης"_var.tcase(); // "Γιάννης"
var= str.fcase() Fold case (lower case and remove accents for indexing)
var= str.normalize() Normalise Unicode to NFC to eliminate different code combinations of the same character
var= str.invert() Simple reversible disguising of text 
"abc"_var.invert(); // "\x{C29EC29DC29C}"
var= str.lower() Convert all FM to VM, VM to SM etc. 
"a1^b2^c3"_var.lower(); // "a1]b2]c3"
var= str.raise() Convert all VM to FM, SM to VM etc. 
"a1]b2]c3"_var.raise(); // "a1^b2^c3"
var= str.crop() Remove any redundant FM, VM etc. characters (Trailing FM; VM before FM etc.) 
"a1^b2]]^c3^^"_var.crop(); // "a1^b2^c3"
var= str.quote() Wrap in double quotes 
"abc"_var.quote(); // ""abc""
var= str.squote() Wrap in single quotes 
"abc"_var.squote(); // "'abc'"
var= str.unquote() Remove one pair of double or single quotes 
"'abc'"_var.unquote(); // "abc"
var= str.trim(trimchars = " ") Remove leading, trailing and excessive inner bytes 
"␣␣a1␣␣b2␣c3␣␣"_var.trim(); // "a1␣b2␣c3"
var= str.trimfirst(trimchars = " ") Ditto leading 
"␣␣a1␣␣b2␣c3␣␣"_var.trimfirst(); // "a1␣␣b2␣c3␣␣"
var= str.trimlast(trimchars = " ") Ditto trailing 
"␣␣a1␣␣b2␣c3␣␣"_var.trimlast(); // "␣␣a1␣␣b2␣c3"
var= str.trimboth(trimchars = " ") Ditto leading, trailing but not inner 
"␣␣a1␣␣b2␣c3␣␣"_var.trimboth(); // "a1␣␣b2␣c3"
var= str.first() Extract first char or "" if empty 
"abc"_var.first(); // "a"
var= str.last() Extract last char or "" if empty 
"abc"_var.last(); // "c"
var= str.first(std::size_t length) Extract up to length leading chars 
"abc"_var.first(2); // "ab"
var= str.last(std::size_t length) Extract up to length trailing chars 
"abc"_var.last(2); // "bc"
var= str.cut(length) Remove length leading chars 
"abcd"_var.cut(2); // "cd"
var= str.paste(pos1, length, insertstr) Insert text at char position overwriting length chars 
"abcd"_var.paste(2, 2, "XYZ"); // "aXYZd"
var= str.paste(pos1, insertstr) Insert text at char position without overwriting any following characters 
"abcd"_var.paste(2, "XYZ"); // "aXYbcd"
var= str.prefix(insertstr) Insert text at the beginning 
"abc"_var.prefix("XY"); // "XYabc"
var= str.pop() Remove one trailing char 
"abc"_var.pop(); // "ab"
var= str.fieldstore(separator, fieldno, nfields, replacement) fieldstore() replaces nfields of subfield(s) in a string. 
"aa*bb*cc*dd"_var.fieldstore("*", 2, 3, "X*Y"); // "aa*X*Y*"

If nfields is 0 then insert fields before fieldno 

"a1*b2*c3*d4"_var.fieldstore("*", 2, 0, "X*Y"); // "a1*X*Y*b2*c3*d4"

If nfields is negative then delete nfields before inserting. 

"a1*b2*c3*d4"_var.fieldstore("*", 2, -3, "X*Y"); // "a1*X*Y"
var= str.substr(pos1, length) substr version 1. Extract length chars starting at pos1 
"abcd"_var.substr(2, 2); // "bc"

If length is negative then work backwards and return chars reversed 

"abcd"_var.substr(3, -2); // "cb"
var= str.substr(pos1) substr version 2. Extract all chars from pos1 up to the end 
"abcd"_var.substr(2); // "bcd"
var= str.b(pos1, length) Same as substr version 1.
var= str.b(pos1) Same as substr version 2.
var= str.convert(fromchars, tochars) Convert chars to other chars one for one or delete where tochars is shorter. 
"abcde"_var.convert("aZd", "XY"); // "Xbce" (a is replaced and d is removed)
var= str.textconvert(fromchars, tochars) Ditto for Unicode code points. 
"a🤡b😀c🌍d"_var.textconvert("🤡😀", "👋"); // "a👋bc🌍d"
var= str.replace(fromstr, tostr) Replace all occurrences of a substr with another. Case sensitive 
"Abc Abc"_var.replace("bc", "X"); // "AX AX"
var= str.replace(regex, tostr) Replace substring(s) using a regular expression.

Use $0, $1, $2 in tostr to refer to groups defined in the regex. 

"A a B b"_var.replace("[A-Z]"_rex, "'$0'"); // "'A' a 'B' b"
var= str.unique() Remove duplicate fields in an FM or VM etc. separated list 
"a1^b2^a1^c2"_var.unique(); // "a1^b2^c2"
var= str.sort(sepchar = FM) Reorder fields in an FM or VM etc. separated list in ascending order 
"20^10^2^1^1.1"_var.sort(); // "1^1.1^2^10^20"

"b1^a1^c20^c10^c2^c1^b2"_var.sort(); // "a1^b1^b2^c1^c10^c2^c20"
var= str.reverse(sepchar = FM) Reorder fields in an FM or VM etc. separated list in descending order 
"20^10^2^1^1.1"_var.reverse(); // "1.1^1^2^10^20"
var= str.shuffle(sepchar = FM) Randomise the order of fields in an FM, VM separated list 
"20^10^2^1^1.1"_var.shuffle(); // "2^1^20^1.1^10" (random order depending on initrand())
var= str.parse(char sepchar = ' ') Replace separator characters with FM char except inside double or single quotes ignoring escaped quotes \\" \&squot; 
"abc,\"def,\"123\" fgh\",12.34"_var.parse(','); // "abc^"def,"123" fgh"^12.34"


String Mutators Not Chainable. All Similar To Non-Mutators
Usage Function Comment
cmd str.ucaser()
cmd str.lcaser()
cmd str.tcaser()
cmd str.fcaser()
cmd str.normalizer()
cmd str.inverter()
cmd str.quoter()
cmd str.squoter()
cmd str.unquoter()
cmd str.lowerer()
cmd str.raiser()
cmd str.cropper()
cmd str.trimmer(trimchars = " ")
cmd str.trimmerfirst(trimchars = " ")
cmd str.trimmerlast(trimchars = " ")
cmd str.trimmerboth(trimchars = " ")
cmd str.firster()
cmd str.laster()
cmd str.firster(std::size_t length)
cmd str.laster(std::size_t length)
cmd str.cutter(length)
cmd str.paster(pos1, length, insertstr)
cmd str.paster(pos1, insertstr)
cmd str.prefixer(insertstr)
cmd str.popper()
cmd str.fieldstorer(sepchar, fieldno, nfields, replacement)
cmd str.substrer(pos1, length)
cmd str.substrer(pos1)
cmd str.converter(fromchars, tochars)
cmd str.textconverter(fromchars, tochars)
cmd str.replacer(regex, tostr)
cmd str.replacer(fromstr, tostr)
cmd str.uniquer()
cmd str.sorter(sepchar = FM)
cmd str.reverser(sepchar = FM)
cmd str.shuffler(sepchar = FM)
cmd str.parser(char sepchar = ' ')


Other String Access
Usage Function Comment
var= str.hash(std::uint64_t modulus = 0) MurmurHash3 hashing. 
"abc"_var.hash(); // 6715211243465481821
var= str.substr(pos1, delimiterchars, out pos2) substr version 3.

Extract a substr starting from pos1 up to any one of the given delimiter chars also returning the next pos1 after the delimiter found

var= str.b(pos1, delimiterchars, out pos2) Alias of substr version 3.
var= str.substr2(io pos1, io delimiterno) substr version 4.

Returns a substr from a given pos1 up to the next RM/FM/VM/SM/TM/STM delimiter char. Also returns the next index/offset and the delimiter no. found 1-6 or 0 if not found.

var= str.b2(io pos1, io delimiterno) Alias of substr version 4
var= str.field(strx, fieldnx = 1, nfieldsx = 1) Extract one or more consecutive fields given a delimiter char or substr. 
"aa*bb*cc"_var.field("*", 2);m // "bb"
var= str.field2(separator, fieldno, nfields = 1) field2 is a version that treats fieldn -1 as the last field, -2 the penultimate field etc. -

TODO Should probably make field() do this (since -1 is basically an erroneous call) and remove field2
Same as var.field() but negative fieldnos work backwards from the last field. 

"aa*bb*cc"_var.field("*", -1); // "cc"


I/O Conversion
Usage Function Comment
var= var.oconv(convstr) Converts internal data to output external display format according to a given conversion code or pattern

If the internal data is invalid and cannot be converted then most conversions return the ORIGINAL data unconverted
Throws a runtime error VarNotImplemented if convstr is invalid
See #ICONV/OCONV PATTERNS 

var(30123).oconv("D/E"); // "21/06/2050"
var= var.iconv(convstr) Converts external data to internal format according to a given conversion code or pattern

If the external data is invalid and cannot be converted then most conversions return the EMPTY STRING ""
Throws a runtime error VarNotImplemented if convstr is invalid
See #ICONV/OCONV PATTERNS 

"21 JUN 2050"_var.iconv("D/E"); // 30123
var= var.format(fmt_str, Args&&... args) Classic format function in printf style

vars can be formatted either with C++ format codes e.g. {:_>8.2f}
or with exodus oconv codes e.g. {::MD20P|R(_)#8} as in the below example. 

var(12.345).format("'{:_>8.2f}' should match '{::MD20P|R(_)#8}'", var(12.345));
// -> "'___12.35' should match '___12.35'"

// or
format("'{:_>8.2f}' should match '{::MD20P|R(_)#8}'", var(12.345), var(12.345));
var= str.from_codepage(codepage) Converts from codepage encoded text to UTF-8 encoded text

e.g. Codepage "CP1124" (Ukrainian).
Use Linux command "iconv -l" for complete list of code pages and encodings. 

"\xa4"_var.from_codepage("CP1124"); // "Є"
// U+0404 Cyrillic Capital Letter Ukrainian Ie Unicode Character
var= str.to_codepage(codepage) Converts to codepage encoded text from UTF-8 encoded text 
"Є"_var.to_codepage("CP1124").oconv("HEX"); // "A4"


Basic Dynamic Array Functions
Usage Function Comment
var= str.f(fieldno, valueno = 0, subvalueno = 0) f() is a highly abbreviated alias for the PICK OS field/value/subvalue extract() function.

"f()" can be thought of as "field" although the function can extract values and subvalues as well.
The convenient PICK OS angle bracket syntax for field extraction (e.g. xxx<20>) is not available in C++.
The abbreviated exodus field extraction function (e.g. xxx.f(20)) is provided instead since field access is extremely heavily used in source code. 

"f1^f2v1]f2v2]f2v3^f2"_var.f(2, 2); // "f2v2"
var= str.extract(fieldno, valueno = 0, subvalueno = 0) Extract a specific field, value or subvalue from a dynamic array.

The alias "f" is usually used instead

var= str.pickreplace(fieldno, valueno, subvalueno, replacement) Same as var.r() function but returns a new string instead of updating a variable in place.
Rarely used.
var= str.pickreplace(fieldno, valueno, replacement) Ditto for a specific multivalue
var= str.pickreplace(fieldno, replacement) Ditto for a specific field
var= str.insert(fieldno, valueno, subvalueno, insertion) Same as var.inserter() function but returns a new string instead of updating a variable in place.
var= str.insert(fieldno, valueno, insertion) Ditto for a specific multivalue
var= str.insert(fieldno, insertion) Ditto for a specific field
var= str.remove(fieldno, valueno = 0, subvalueno = 0) Same as var.remover() function but returns a new string instead of updating a variable in place.

"remove" was called "delete" in Pick OS.


Dynamic Array Filters
Usage Function Comment
var= str.sum() Sum up multiple values into one higher level 
"1]2]3^4]5]6"_var.sum(); // "6^15"
var= str.sumall() Sum up all levels into a single figure 
"1]2]3^4]5]6"_var.sumall(); // "21"
var= str.sum(sepchar) Ditto allowing commas etc. 
"10,20,33"_var.sum(","); // "60"
var= str.mv(opcode, var2) Binary ops (+, -, *, /) in parallel on multiple values 
"10]20]30"_var.mv("+","2]3]4"); // "12]23]34"


Dynamic Array Mutators (Standalone And Cannot Be Chained)
Usage Function Comment
cmd str.r(fieldno, replacement) Replaces a specific field in a dynamic array 
var v1 = "f1^v1]v2}s2}s3^f3"_var;
v1.r(2, 2, "X"); // v1 -> "f1^X^f3"
cmd str.r(fieldno, valueno, replacement) Ditto for specific value in a specific field. 
var v1 = "f1^v1]v2}s2}s3^f3"_var;
v1.r(2, 2, "X"); // v1 -> "f1^v1]X^f3"
cmd str.r(fieldno, valueno, subvalueno, replacement) Ditto for a specific subvalue in a specific value of a specific field 
var v1 = "f1^v1]v2}s2}s3^f3"_var;
v1.r(2, 2, 2, "X"); // v1 -> "f1^v1]v2}X}s3^f3"
cmd str.inserter(fieldno, insertion) Insert a specific field in a dynamic array, moving all other fields up. 
var v1 = "f1^v1]v2}s2}s3^f3"_var;
v1.inserter(2, "X"); // v1 -> "f1^X^v1]v2}s2}s3^f3"
cmd str.inserter(fieldno, valueno, insertion) Ditto for a specific value in a specific field, moving all other fields up. 
var v1 = "f1^v1]v2}s2}s3^f3"_var;
v1.inserter(2, 2, "X"); // v1 -> "f1^v1]X]v2}s2}s3^f3"
cmd str.inserter(fieldno, valueno, subvalueno, insertion) Ditto for a specific subvalue in a dynamic array, moving all other subvalues up. 
var v1 = "f1^v1]v2}s2}s3^f3"_var;
v1.inserter(2, 2, 2, "X"); // v1 -> "f1^v1]v2}X}s2}s3^f3"
cmd str.remover(fieldno, valueno = 0, subvalueno = 0) Remove a specific field (or value, or subvalue) from a dynamic array, moving all other fields (or values, or subvalues) down. 
var v1 = "f1^v1]v2}s2}s3^f3"_var;
v1.remover(2, 2); // v1 -> "f1^v1^f3"


Dynamic Array Search
Usage Function Comment
if str.locate(target) locate() with only the target substr argument provided searches unordered values separated by VM chars.

Returns true if found and false if not. 

if ("UK]US]UA"_var.locate("US")) ... // true
if str.locate(target, out valueno) locate() with only the target substr and valueno arguments provided searches unordered values separated by VM chars.

Returns true if found and with the value number in valueno.
Returns false if not found and with the max value number + 1 in setting. Suitable for additiom of new values 

var valueno; if ("UK]US]UA"_var.locate("US", valueno)) ... // returns true and valueno = 2
if str.locate(target, out setting, fieldno, valueno = 0) locate() the target in unordered fields if fieldno is 0, or values if a fieldno is specified, or subvalues if the valueno argument is provided.

Returns true if found and with the field, value or subvalue number in setting.
Returns false if not found and with the max field, value or subvalue number found + 1 in setting. Suitable for replacement of new fields, values or subvalues. 

var setting; if ("f1^f2v1]f2v2]s1}s2}s3}s4^f3^f4"_var.locate("s4", setting, 2, 3)) ... // returns true and setting = 4
if str.locateby(ordercode, target, out valueno) locateby() without fieldno or valueno arguments searches ordered values separated by VM chars.

The order code can be AL, DL, AR, DR meaning Ascending Left, Descending Right, Ascending Right, Ascending Left.
Left is used to indicate alphabetic order where 10 < 2.
Right is used to indicate numeric order where 10 > 2.
Data must be in the correct order for searching to work properly.
Returns true if found.
In case the target is not exactly found then the correct value no for inserting the target is returned in setting. 

var valueno; if ("aaa]bbb]ccc"_var.locateby("AL", "bb", valueno)) ... // returns false and valueno = 2 where it could be correctly inserted.
if str.locateby(ordercode, target, out setting, fieldno, valueno = 0) locateby() ordered as above but in fields if fieldno is 0, or values in a specific fieldno, or subvalues in a specific valueno. 
var setting; if ("f1^f2^aaa]bbb]ccc^f4"_var.locateby("AL", "bb", setting, 3)) ... // returns false and setting = 2 where it could be correctly inserted.
if str.locateusing(usingchar, target) locate() a target substr in the whole unordered string using a given delimiter char returning true if found.
if (
"AB,EF,CD"_var.locateusing(",", "EF")) ... // true
if str.locateusing(usingchar, target, out setting, fieldno = 0, valueno = 0, subvalueno = 0) locate() the target in a specific field, value or subvalue using a specified delimiter and unordered data

Returns true If found and returns in setting the number of the delimited field found.
Returns false if not found and returns in setting the maximum number of delimited fields + 1 if not found.
This is similar to the main locate command but the delimiter char can be specified e.g. a comma or TM etc. 

var setting; if ("f1^f2^f3c1,f3c2,f3c3^f4"_var.locateusing(",", "f3c2", setting, 3)) ... // returns true and setting = 2
if str.locatebyusing(ordercode, usingchar, target, out setting, fieldno = 0, valueno = 0, subvalueno = 0) locatebyusing() supports all the above features in a single function.

Returns true if found.


Database Access
Usage Function Comment
if conn.connect(conninfo = "") For all db operations, var() can be db connection created with dbconnect() or any var will perform a default connection.

The db connection string (conninfo) parameters are merged from the following places in descending priority.
1. Provided in connect()'s conninfo argument. See 4. for the complete list of parameters.
2. Any environment variables EXO_HOST EXO_PORT EXO_USER EXO_DATA EXO_PASS EXO_TIME
3. Any parameters found in a configuration file at ~/.config/exodus/exodus.cfg
4. The defaults "host=127.0.0.1 port=5432 dbname=exodus user=exodus password=somesillysecret connect_timeout=10" 

var db="mydb";
if (not db.connect()) abort(db.lasterror());
db.version().outputl();
db.disconnect();
cmd conn.disconnect() Removes a db connection and frees resources.
cmd conn.disconnectall() Removes all db connection and frees resources.
if conn.attach(filenames) Attach (connect) specific files by name to specific connections.

For the remainder of the session, opening the file by name will automatically use the specified connection.

cmd conn.detach(filenames) Detach (disconnect) files that have been attached using attach().
if conn.begintrans() Begin a db transaction.
if conn.rollbacktrans() Rollback a db transaction.
if conn.committrans() Commit a db transaction.
if conn.statustrans() Check if a db transaction is in progress.
if conn.sqlexec(sqlcmd) Execute an sql command.
if conn.sqlexec(sqlcmd, io response) Execute an SQL command and capture the response.
var= conn.lasterror() Get the last os or db error message.
var= conn.loglasterror(source = "") Log the last os or db error message.


Database Management
Usage Function Comment
if conn.dbcreate(dbname) Create a named database on a particular connection.
var= conn.dblist() Return a list of available databases on a particular connection.
if conn.dbcopy(from_dbname, to_dbname) Create a named database from an existing database.
if conn.dbdelete(dbname) Delete (drop) a named database.
if conn.createfile(filename) Create a named db file.
if conn.renamefile(filename, newfilename) Rename a db file.
if conn.deletefile(filename) Delete (drop) a db file
if conn.clearfile(filename) Delete all records in a db file
var= conn.listfiles() Return a list of all files in a database
var= conn.reccount(filename = "") Returns the approx. number of records in a file
if conn.flushindex(filename = "") Calls db maintenance function (vacuum)

This doesnt flush any indexes any longer but does make sure that reccount() function is reasonably accurate.


Database File I/O
Usage Function Comment
if file.open(dbfilename, connection = "")
cmd file.close()
if file.createindex(fieldname, dictfile = "")
if file.deleteindex(fieldname)
var= file.listindex(filename = "", fieldname = "")
var= file.lock(key) Returns 1=ok, 0=failed, ""=already locked
if file.unlock(key)
if file.unlockall()
if rec.read(file, key) Reads a record from a file given its unique primary key.

Returns false if the key doesnt exist 

var rec; if (not rec.read(file, key)) ...
cmd rec.write(file, key) Writes a record to a file.

It updates an existing record if the key already exists or inserts a new record.
It always succeeds so no result code is returned.
Any memory cached record is deleted. 

rec.write(file, key);
if rec.updaterecord(file, key) Updates an existing record in a file.

Returns false if the key doesnt already exist
Any memory cached record is deleted. 

if (not rec.updaterecord(file, key)) ...
if rec.insertrecord(file, key) Inserts a new record in a file.

Returns false if the key already exists
Any memory cached record is deleted. 

if (not rec.insertrecord(file, key)) ...
if file.deleterecord(key) Deletes a record from a file given its key.

Returns false if the key doesnt exist
Any memory cached record is deleted.

if (not file.deleterecord(key)) ...
if str.readf(file, key, fieldno) Same as read() but only returns a specific field no from the record 
var field; if (not field.readf(file, key, fieldno)) ...
cmd str.writef(file, key, fieldno) Same as write() but only writes a specific field no to the record 
field.writef(file, key, fieldno);
if rec.readc(file, key) Cache read a record from a memory cache "file" given its key.

1. Tries to read from a memory cache and returns true if successful.
2. Reads to read from the actual file and returns false if unsuccessful.
3. Writes the record and key to the memory cache and returns true.
Cached db file data lives in exodus process memory not the database. 

var rec; if (not rec.readc(file, key)) ...
cmd rec.writec(file, key) Cache write a record and key into a memory cached "file".

The actual file is NOT updated.
It either updates an existing record if the key already exists or otherwise inserts a new record.
It always succeeds so no result code is returned. 

rec.writec(file, key);
if dbfile.deletec(key) Deletes a record and key from a memory cached "file".

The actual file is NOT updated.
Returns false if the key doesnt exist 

if (not file.deletec(key)) ...
cmd conn.cleardbcache() Clears the memory cache of all records for the given connection

All future cache readc() function calls will be forced to obtain records from the actual database and refresh the cache. 

conn.cleardbcache();
var= str.xlate(filename, fieldno, mode)


Database Sort/Select
Usage Function Comment
if file.select(sortselectclause = "")
cmd file.clearselect()
if file.hasnext()
if file.readnext(out key)
if file.readnext(out key, out valueno)
if file.readnext(out record, out key, out valueno)
if file.savelist(listname)
if file.getlist(listname)
if file.makelist(listname, keys)
if file.deletelist(listname)
if file.formlist(keys, fieldno = 0)


OS Time/Date
Usage Function Comment
var= var.date() Number of whole days since pick epoch 1967-12-31 00:00:00 UTC. Negative for dates before. 
var today1 = var().date(); // e.g. was 20821 from 2025-01-01 00:00:00 UTC
// or just
var today2 = date();
var= var.time() Number of whole seconds since last 00:00:00 (UTC). 
var now1 = var().time(); // range 0 - 86399 since there are 24*60*60 (86400) seconds in a day.
// or just
var now2 = time();
var= var.ostime() Number of fractional seconds since last 00:00:00 (UTC).

A floating point with approx. nanosecond resolution depending on hardware. 

var now1 = var().ostime(); // e.g. 23343.704387955 approx. 06:29:03 UTC
// or just
var now2 = ostime();
var= var.timestamp() Number of fractional days since pick epoch 1967-12-31 00:00:00 UTC. Negative for dates before.

A floating point with approx. nanosecond resolution depending on hardware. 

var now1 = var().timestamp(); // was 20821.99998842593 around 2025-01-01 23:59:59 UTC
// or just
var now2 = ostimestamp();
var= var.timestamp(ostime) Construct a timestamp from a date and time 
var ts1 = var().timestamp(iconv("2025-01-01", "D"), iconv("23:59:59", "MT")); // 20821.99998842593
// or just
var ts2 = timestamp(somedate, sometime);
cmd var.ossleep(milliseconds) Sleep/pause/wait for a number of milliseconds 
var().ossleep(3000); // sleep for 3 seconds
// or just
ossleep(3000);
var= var.oswait(milliseconds, directory) Sleep/pause/wait for any activity in a file system directory for a number of milliseconds 
var().oswait(3000, "."); // max 3 seconds
// or just
oswait(3000, ".");


OS File Io
Usage Function Comment
if osfilevar.osopen(osfilename, locale = "") Given the name of an existing file name including path, initialises a var that can be used in random access osbread and osbwrite functions.

Optionally allows specifying a locale/codepage to which and from which all writes and reads will be converted (?) from a assumed internal UTF8 encoding.
File will be opened for writing if possible otherwise for reading.
Returns true if successful or false if not possible for any reason.
e.g. Target doesnt exist, permissions etc. 

var hostsfile;
if (not hostsfile.osopen("/etc/hosts") ...
// or
if (not osopen("/etc/hosts" to hostsfile) ...
if osfilevar.osbread(osfilevar, io offset, length) Reads length bytes from an existing os file starting at a given byte offset (0 based).

The osfilevar file handle may either be initialised by osopen (optionally with a locale/codepage) or be just a normal string variable holding the path and name of the os file.
After reading, the offset is updated to point to the correct offset for a subsequent sequential read.
If reading utf8 data then the length of data actually returned may be a few bytes shorter than requested in order to be a complete number of UTF-8 code points. 

var text, hostsfile = "/etc/hosts", offset = 0;
if (not text.osbread(hostsfile, offset, 1024) ...
// or
if (not osbread(text from hostsfile, offset, 1024) ...
if osfilevar.osbwrite(osfilevar, io offset) Writes data to an existing os file starting at a given byte offset (0 based).

See osbread for more info. 

let text = "\n#comment", xyzfile = "../xyz.conf";
var offset = osfile(xyzfile).f(1); // size of file -> append
if (not text.osbwrite(xyzfile, offset)) abort(lasterror());
// or
if (not osbwrite(text on xyzfile, offset) ...
cmd osfilevar.osclose() Removes an osfilevar handle from the internal memory cache of os file handles freeing up both exodus process memory and operating system resources.

It is advisable to osclose any file handles after use, regardless of whether they were specifically opened using osopen or not, especially in long running programs. Exodus performs caching of internal os file handles per thread and os file. If not closed, then the operating system will probably not flush deleted files from storage until the process is terminated. This can potentially create an memory issue or file system resource issue especially if osopening/osreading/oswriting many perhaps temporary files in a long running process. 

osfilevar.osclose();
// or
osclose(osfilevar);
if str.osread(osfilename, codepage = "") Read a complete os file into a var

Returns true if successful or false if not possible for any reason.
e.g. File doesnt exist, permissions etc. 

var text;
if (not text.osread("/etc/hosts")) ...
// or
if (not osread(text from "/etc/hosts")) ...
if str.oswrite(osfilename, codepage = "") Create a complete os file from a var.

Any existing file is removed first.
Returns true if successful or false if not possible for any reason.
e.g. Path is not writeable, permissions etc. 

let text = "xyz = 123\n", osfilename="../xyz.conf";
if (not text.oswrite(osfilename)) abort(lasterror());
// or
if (not oswrite(text on osfilename)) ...
if osfilename.osremove() Removes/deletes an os file from the OS file system given path and name.

Will not remove directories. Use osrmdir() to remove directories
Returns true if successful or false if not possible for any reason.
e.g. Target doesnt exist, path is not writeable, permissions etc. 

if (not "../xyz.conf"_var.osfilevar.osremove()) abort(lasterror());
// or
if (not osremove("../xyz.conf") ...
if osfileordirname.osrename(new_dirpath_or_filepath) Renames an os file or dir in the OS file system.

Will not overwrite an existing file or dir.
Source and target must exist in the same storage device.
Returns true if successful or false if not possible for any reason.
e.g. Target already exists, path is not writeable, permissions etc.
Uses std::filesystem::rename internally. 

if (not "../xyz.conf"_var.osfilevar.osrename("../abc.conf")) abort(lasterror());
// or
if (not osrename("../xyz.conf", "../abc.conf") ...
if osfileordirname.oscopy(to_osfilename) Copies a file or directory recursively within the file system.

Uses std::filesystem::copy internally with recursive and overwrite options 

if (not "../xyz.conf"_var.osfilevar.oscopy("../abc.conf")) abort(lasterror());
// or
if (not oscopy("../xyz.conf", "../abc.conf") ...
if osfileordirname.osmove(to_osfilename) "Moves" a file or dir within the os file system.

Will not overwrite an existing file or dir.
Returns true if successful or false if not possible for any reason.
e.g. Source doesnt exist or cannot be accessed, target already exists, source or target is not writeable, permissions etc.
Attempts osrename first then oscopy followed by osremove original. 

if (not "../xyz.conf"_var.osfilevar.osmove("../abc.conf")) abort(lasterror());
// or
if (not osmove("../xyz.conf", "../abc.conf") ...


OS Directories
Usage Function Comment
var= dirpath.oslist(globpattern = "", mode = 0) Returns a FM delimited string containing all matching dir entries given a dir path

A glob pattern (e.g. *.conf) can be appended to the path or passed as argument. 

var entries1 = "/etc/"_var.oslist("*.cfg"); // "adduser.conf^ca-certificates.conf^ ..."
// or just
var entries2 = oslist("/etc/" "*.conf";
var= dirpath.oslistf(globpattern = "") Same as oslist for files only
var= dirpath.oslistd(globpattern = "") Same as oslist for files only
var= osfileordirpath.osinfo(mode = 0) Return dir info for any dir entry or "" if it doesnt exist

A short string containing size ^ FM ^ modified_time ^ FM ^ modified_time
mode 0 default
mode 1 returns "" if not a file
mode 2 returns "" if not a dir
See also osfile() and osdir() 

var info1 = "/etc/hosts"_var.osinfo(); // "221^20597^78309"
// or just
var info2 = osinfo("/etc/hosts");
var= osfilename.osfile() Return dir info for a file

A short string containing size ^ FM ^ modified_time ^ FM ^ modified_time
Alias for osinfo(1) 

var fileinfo1 = "/etc/hosts"_var.osfile(); // "221^20597^78309"
// or just
var fileinfo2 = osfile("/etc/hosts");
var= dirpath.osdir() Return dir info for a dir.

A short string containing FM ^ modified_time ^ FM ^ modified_time
Alias for osinfo(2) 

var dirinfo1 = "/etc/"_var.osdir(); // "^20848^44464"
// or just
var dirinfo2 = osfile("/etc/");
if dirpath.osmkdir() Makes a new directory and returns true if successful.

Including parent dirs if necessary. 

if (not "abc/def"_var.osmkdir()) ...
// or just
if (not osmkdir("abc/def")) ...
if dirpath.osrmdir(evenifnotempty = false) Removes a os dir and returns true if successful.

Optionally even if not empty. Including subdirs. 

if (not "abc/def"_var.osrmdir()) ...
// or just
if (not osrmdir("abc/def")) ...
var= var.oscwd() Returns the current working directory 
var cwd1 = var().oscwd(); // "/home/exodus"
// or just
var cwd2 = oscwd();
if var.oscwd(newpath) Changes the current working dir and returns true if successful. 
if (not "abc/def"_var.oscwd()) ...
// or just
if (not oscwd("abc/def")) ...


OS Shell/Environment
Usage Function Comment
if command.osshell() Execute a shell command

Returns true if the process terminates with error status 0 and false otherwise. 

let cmd = "ls -l xyz";
if (not cmd.osshell()) ...
// or
if (not osshell(cmd)) ...
if instr.osshellread(oscmd) Same as osshell but captures stdout 
var intext;
if (not intext.osshellread("ls -l xyz")) ...

// or just capturing stdout but ignoring exit status
intext = osshellread("ls -l xyz");
if outstr.osshellwrite(oscmd) Same as osshell but provides stdin to the process 
var outtext = ...
if (not outtext.osshellwrite("grep xyz")) ...
// or
if (not osshellwrite(outtext, "grep xyz")) ...
var= var.ostempdirpath() Get the path of the tmp dir 
var v1 = var().ostempdirpath(); // "/tmp/"
// or just
var v1 = ostempdirpath();
()
var= var.ostempfilename() Create and get a temporary file 
var tempfilename1 = var().ostempfilename(); // "/tmp/~exoEcLj3C"
// or just
var tempfilename2 = ostempfilename();
()
if envvalue.osgetenv(envcode) Get the value of an environment variable 
var envvalue1;
if (not envvalue1.osgetenv("HOME")) ... // "/home/exodus"
// or just
var envvalue2 = osgetenv("HOME");
cmd envvalue.ossetenv(envcode) Set the value of an environment variable code 
envvalue.ossetenv(envcode);
// or just
ossetenv(envcode, envvalue);
var= var.ospid() Get the os process id 
let pid = var().ospid(); // 663237
// or just
let pid = ospid();
var= var.ostid() Get the os thread process id 
let tid = var().ostid(); // 663237
// or just
let tid = ostid();
var= var.version() Get the libexodus build date and time 
var().version(); // "29 JAN 2025 14:56:52"


Output
Usage Function Comment
expr var.output() stdout no new line, buffered
expr var.outputl() stdout starts a new line, flushed
expr var.outputt() stdout adds a tab, buffered
expr var.logput() stdlog no new line, buffered
expr var.logputl() stdlog starts a new line, flushed
expr var.errput() stderr no new line, flushed
expr var.errputl() stderr starts a new line, flushed
expr var.output(prefix) stdout with a prefix, no new line, buffered
expr var.outputl(prefix) stdout with a prefix, starts a new line, flushed
expr var.outputt(prefix) stdout with a prefix, adds a tab, buffered
expr var.logput(prefix) stdlog with a prefix, no new line, buffered
expr var.logputl(prefix) stdlog with a prefix, starts a new line, flushed
expr var.errput(prefix) stderr with a prefix, no new line, flushed
expr var.errputl(prefix) stderr with a prefix, starts a new line, flushed
expr var.put(std::ostream& ostream1) Output to a given stream
cmd var.osflush() Flushes any buffered output to stdout/cout 
var().osflush();
// or just
osflush();
()


Standard Input
Usage Function Comment
expr var.input() Wait for stdin until cr or eof
expr var.input(prompt) Ditto after outputting prompt to stdout
expr var.inputn(nchars) Wait for nbytes from stdin
if var.isterminal() true if terminal is available
if var.hasinput(milliseconds = 0) true if stdin bytes available within milliseconds
if var.eof() true if stdin is at end of file
if var.echo(on_off) Reflect all stdin to stdout if terminal available
cmd var.breakon() Allow interrupt Ctrl+C
cmd var.breakoff() Prevent interrupt Ctr+C
Retrieved from "https://devwiki.neosys.com/index.php?title=Manual&oldid=1561"