Qore Util Module Reference  1.8
Util Namespace Reference

the Util namespace contains all the objects in the Util module More...

Classes

hashdecl  UriQueryInfo
 the return value of the parse_uri_query() function More...
 
hashdecl  UrlRetrievalOptions
 URL retrieval options for get_file_from_url() More...
 

Functions

bool absolute_path (string path)
 returns True if the argument is an absolute path, False if not More...
 
bool absolute_path_unix (string path)
 returns True if the argument is a UNIX absolute path, False if not More...
 
bool absolute_path_windows (string path)
 returns True if the argument is a Windows absolute path, False if not More...
 
bool check_ip_address (string ip, bool exception=False)
 verifies if a string is an IPv4 or IPv6 address More...
 
int compare_version (string lv, string rv)
 compares complex versions by breaking down strings into component parts More...
 
list< auto > flatten (softlist< auto > arg)
 Flattens a nested list (the nesting can be to any depth). More...
 
string get_byte_size (softnumber n, int decimals=2)
 returns a string giving a user-friendly real storage size (ie based on 1KiB = 1024 bytes) in KiB, MiB, GiB, TiB, etc for the given byte size More...
 
string get_exception_string (hash< auto > ex)
 returns a multi-line string from the exception hash argument suitable for logging or output on the console More...
 
data get_file_from_ftp (string url, string path, *hash< UrlRetrievalOptions > options)
 Retrieves file data from an FTP URL and a path. More...
 
data get_file_from_http (string url, *string path, *hash< UrlRetrievalOptions > options)
 Retrieves file data from an HTTP URL. More...
 
data get_file_from_sftp (string url, string path, *hash< UrlRetrievalOptions > options)
 Retrieves file data from an SFTP URL and a path. More...
 
data get_file_from_url (string url, *hash< UrlRetrievalOptions > options)
 Retrieves file data from the given URL. More...
 
data get_local_file (string path, *hash< UrlRetrievalOptions > options)
 Retrieves file data from a local file path. More...
 
string get_marketing_byte_size (softnumber n, int decimals=2)
 returns a string giving a user-friendly "marketing storage" size (ie based on 1KB = 1000 bytes) in KB, MB, GB, TB, etc for the given byte size More...
 
string get_random_string (softint len=15, int level=3)
 function that returns a random string More...
 
string get_relative_path (string basedir, string path, string cwd=getcwd())
 returns a path as a relative path from another directory More...
 
string glob_to_regex (string pat)
 Translates a shell pattern to a regular expression. More...
 
bool is_float (string text, bool pure=False)
 Checks whether string represents a (true) float value. More...
 
bool is_int (string text, bool pure=False)
 Checks whether string represents a (true) integer value. More...
 
bool is_number (string text, bool pure=False)
 Checks whether string represents a (true) number value. More...
 
string lpad (softstring text, int length, string padding=' ')
 Returns a string left-padded to a specified length with the specified characters. More...
 
string make_uri_query (hash< UriQueryInfo > h, string arg_separator=';')
 returns a serialized string for a UriQueryInfo hash More...
 
string normalize_dir (string path, string cwd=getcwd())
 returns a platform-specific normalized path name (starting from /, eliminates ".", "..", and "//") More...
 
string normalize_dir_unix (string path, string cwd=getcwd())
 returns a normalized UNIX path name (starting from /, eliminates ".", "..", and "//") More...
 
string normalize_dir_windows (string path, string cwd=getcwd())
 returns a normalized Windows path name (eliminates ".", "..", and "//") More...
 
string ordinal (int i)
 Returns string with partially textual representation of ordinal integer value. More...
 
int parse_memory_size (string str, *bool use_binary)
 Returns a size in bytes from a string where "1M" = 1048576 and so forth. More...
 
list< intparse_ranges (string text)
 Parses a string and returns a list of integers. More...
 
auto parse_to_qore_value (string arg)
 tries to convert a string (such as an argument given from the command-line) to a Qore value More...
 
hash< UriQueryInfoparse_uri_query (string path)
 parses a URI path for a arguments and a method; where the method is the part of the path before the first "?" character, and arguments are after More...
 
string plural (int count, string base, string singular='', string plural='s')
 Returns string with number and proper singular/plural form of noun. More...
 
string regex_escape (string text)
 Escapes (backslashes) all non-alphanumeric characters in a string. More...
 
string rpad (softstring text, int length, string padding=' ')
 Returns a string right-padded to a specified length with the specified characters. More...
 
bool same (list< auto > l)
 checks whether given list has only unique elements More...
 
string serialize_to_string (auto val)
 Serializes the given value to a string that can be deserialized with parse_to_qore_value() More...
 
list< auto > slice (list< auto > l, softlist< auto > indices)
 list slice implementation More...
 
bool string_ends_with (string str, string substr)
 Verifies whether a string ends with specific substring. More...
 
bool string_starts_with (string str, string substr)
 Verifies whether a string begins with specific substring. More...
 
string substitute_env_vars (string str)
 Substitutes environment variables in a string and returns the string. More...
 
string tmp_location ()
 Returns a path for temporary files. More...
 
list< auto > uniq (softlist< auto > arg)
 Returns a duplicate-free version of the list. More...
 
list< auto > zip ()
 Returns a list of lists, where the i-th list contains the i-th element from each of the argument lists. More...
 

Variables

const StorageAbbr = map {$1[0].lwr(): $#}
 hash of single-letter storage name abbreviations
 
const StorageNames = ("Kilo", "Mega", "Giga", "Tera", "Peta", "Exa", "Zetta", "Yotta", "Bronto")
 storage names (Geop, which would normally follow Bronto, is excluded as the abbreviation would be GB/GiB)
 

Detailed Description

the Util namespace contains all the objects in the Util module

Function Documentation

◆ absolute_path()

bool Util::absolute_path ( string  path)

returns True if the argument is an absolute path, False if not

Example:
bool abs = absolute_path(path);
Parameters
paththe path to check
Returns
True if the argument is an absolute path, False if not
See also
Qore::absolute_path()
Note
this function has been moved to the Qore library and is reexported here for backwards-compatibility

◆ absolute_path_unix()

bool Util::absolute_path_unix ( string  path)

returns True if the argument is a UNIX absolute path, False if not

Example:
bool abs = absolute_path_unix(path);
Parameters
paththe path to check
Returns
True if the argument is a UNIX absolute path, False if not
See also
Qore::absolute_path_unix()
Note
this function has been moved to the Qore library and is reexported here for backwards-compatibility

◆ absolute_path_windows()

bool Util::absolute_path_windows ( string  path)

returns True if the argument is a Windows absolute path, False if not

Example:
bool abs = absolute_path_windows(path);
Parameters
paththe path to check
Returns
True if the argument is a Windows absolute path, False if not
See also
Qore::absolute_path_windows()
Note
this function has been moved to the Qore library and is reexported here for backwards-compatibility

◆ check_ip_address()

bool Util::check_ip_address ( string  ip,
bool  exception = False 
)

verifies if a string is an IPv4 or IPv6 address

Example:
check_ip_address(str, True);
Parameters
ipthe string in dot-notation (for IPv4 addresses) or colon notation (for IPv6 addresses) to check; the string should not contain any network component which would cause the comparison to fail; note that IPv4 address components must be in the range of 0 - 255 and must not have leading zeros
exceptionif True an exception will be thrown if the string is not a valid IPv4 or IPv6 address, if False the return value of the function indicates the string's validation status
Returns
True if the string is a valid IPv4 or IPv6 address, False if not (note that if exception is True then an INVALID-IP-ADDRESS exception is thrown if the string is invalid)
Exceptions
INVALID-IP-ADDRESSthis exception is thrown if ip is not a valid IPv4 or IPv6 address and exception is True
Since
Util 1.4

◆ compare_version()

int Util::compare_version ( string  lv,
string  rv 
)

compares complex versions by breaking down strings into component parts

Example:
int result = compare_version("2.11.1", "2.2");

Each element is compared separately, so that compare_version("2.11.1", "2.2") returns 1 (a regular string comparison would give the opposite result)

Parameters
lvleft-hand version
rvright-hand version
Returns
-1 if lv < rv, 0 if equal, and 1 if lv > rv

◆ flatten()

list<auto> Util::flatten ( softlist< auto >  arg)

Flattens a nested list (the nesting can be to any depth).

Parameters
arga list to flatten
Returns
a flattened list
Example:
list<int> f = flatten(((1, 2), (3, 4), 5)); # returns (1, 2, 3, 4, 5)
Since
Util 1.3

◆ get_byte_size()

string Util::get_byte_size ( softnumber  n,
int  decimals = 2 
)

returns a string giving a user-friendly real storage size (ie based on 1KiB = 1024 bytes) in KiB, MiB, GiB, TiB, etc for the given byte size

Example:
string str = get_byte_size(n);
Parameters
nthe number to display
decimalsthe number of digits after the decimal point

◆ get_exception_string()

string Util::get_exception_string ( hash< auto >  ex)

returns a multi-line string from the exception hash argument suitable for logging or output on the console

Parameters
exthe exception hash to process
Returns
a multi-line string from the exception hash argument suitable for logging or output on the console

◆ get_file_from_ftp()

data Util::get_file_from_ftp ( string  url,
string  path,
*hash< UrlRetrievalOptions options 
)

Retrieves file data from an FTP URL and a path.

Parameters
urlthe FTP URL
paththe path to the file on the FTP server
optionsconnection options
Exceptions
GET-FILE-FROM-URL-ERRORempty path string
Since
Util 1.5

◆ get_file_from_http()

data Util::get_file_from_http ( string  url,
*string  path,
*hash< UrlRetrievalOptions options 
)

Retrieves file data from an HTTP URL.

Parameters
urlthe HTTP URL including the path to the resource to retrieve
pathan optional path to append to the URL
optionsconnection options
Since
Util 1.5

◆ get_file_from_sftp()

data Util::get_file_from_sftp ( string  url,
string  path,
*hash< UrlRetrievalOptions options 
)

Retrieves file data from an SFTP URL and a path.

Parameters
urlthe SFTP URL
paththe path to the file on the SFTP server
optionsconnection options
Exceptions
GET-FILE-FROM-URL-ERRORempty path string
Since
Util 1.5

◆ get_file_from_url()

data Util::get_file_from_url ( string  url,
*hash< UrlRetrievalOptions options 
)

Retrieves file data from the given URL.

Parameters
urlthe URL for the file
optionsretrieval options
Exceptions
GET-FILE-FROM-URL-ERRORunknown or unsupported scheme in URL or other error retrieving the file
Since
Util 1.5

◆ get_local_file()

data Util::get_local_file ( string  path,
*hash< UrlRetrievalOptions options 
)

Retrieves file data from a local file path.

Parameters
paththe path to the file data on the local filesystem
optionsconnection options
Since
Util 1.5

◆ get_marketing_byte_size()

string Util::get_marketing_byte_size ( softnumber  n,
int  decimals = 2 
)

returns a string giving a user-friendly "marketing storage" size (ie based on 1KB = 1000 bytes) in KB, MB, GB, TB, etc for the given byte size

Example:
string str = get_marketing_byte_size(n);
Parameters
nthe number to display
decimalsthe number of digits after the decimal point

◆ get_random_string()

string Util::get_random_string ( softint  len = 15,
int  level = 3 
)

function that returns a random string

Example:
string pass = get_random_string();
Parameters
lenthe length fo the string returned
levela value from 1 - 4 inclusive giving the range of printable ASCII characters included in the output (values out of the range result in the nearest value in the range being used):
  • 1: only upper case
  • 2: +lower case
  • 3: +numbers
  • 4: +symbols but not including any quote characters
Returns
a random string of the given length containing only printable ASCII characters according to the level argument
See also
Qore::get_random_bytes()

◆ get_relative_path()

string Util::get_relative_path ( string  basedir,
string  path,
string  cwd = getcwd() 
)

returns a path as a relative path from another directory

Example:
string path = get_relative_path("/var/tmp", path);
Parameters
basedirthe directory that the result will be relative to
paththe path to return as a relative path from base
cwdthe current working directory, used in case base or path are relative paths
Returns
a path as a relative path from another directory
Since
Util 1.8

◆ glob_to_regex()

string Util::glob_to_regex ( string  pat)

Translates a shell pattern to a regular expression.

Returns the shell-style pattern converted to a regular expression.

Parameters
patthe pattern to convert
Returns
a converted pattern
Example:
string s = glob_to_regex ("*.*"); # returns ".*\\..*"
Since
Util 1.2

◆ is_float()

bool Util::is_float ( string  text,
bool  pure = False 
)

Checks whether string represents a (true) float value.

Parameters
texta string to check
pureif True then only floats match, otherwise include integers.
Returns
True if input represents a float value, False otherwise.
Example:
bool match = is_float("1.2");
# returns True, while any of the following returns False:
match = is_float("12", True);
match = is_float("1.2x");
Note
The function only checks whether a string represents a float value, but it does not validate size / precision restrictions (whether it would fit Qore's native float type).
Since
Util 1.2

◆ is_int()

bool Util::is_int ( string  text,
bool  pure = False 
)

Checks whether string represents a (true) integer value.

Parameters
texta string to check
pureif True then only integers match, otherwise check floats too.
Returns
True if input represents an integer value, False otherwise.
Example:
bool match = is_int("123");
# returns True, while any of the following returns False:
match = is_int("1.0", True);
match = is_int("12x");
Note
The function only checks whether a string represents an integer value, but it does not validate size restrictions (that is whether it would fit Qore's native int type) etc.
Since
Util 1.2

◆ is_number()

bool Util::is_number ( string  text,
bool  pure = False 
)

Checks whether string represents a (true) number value.

Parameters
texta string to check
pureif True then only numbers match, otherwise include floats and integers.
Returns
True if input represents a number value, False otherwise.
Example:
bool match = is_number("1.2n");
# returns True, while any of the following returns False:
match = is_number("12", True);
match = is_number("1.2", True);
match = is_number("1.2x");
Note
The function only checks whether a string represents an arbitrary precision number value, but it does not validate any restrictions (whether it would fit Qore's native number type).
Since
Util 1.2

◆ lpad()

string Util::lpad ( softstring  text,
int  length,
string  padding = ' ' 
)

Returns a string left-padded to a specified length with the specified characters.

Returns a string, left-padded to a specified length with the specified characters; or, when the string to be padded is longer than the length specified after padding, only that portion of the string that fits into the specified length.

Parameters
textinput string that you want to pad
lengthtotal length of output string (in characters)
paddingpadding character(s); default value is a single blank
Returns
a string left-padded to the specified length
Example:
string s = lpad ("123", 5); # returns " 123"
string s = lpad ("ABC", 9, "-"); # returns "------ABC"
Since
Util 1.2

◆ make_uri_query()

string Util::make_uri_query ( hash< UriQueryInfo h,
string  arg_separator = ';' 
)

returns a serialized string for a UriQueryInfo hash

Parameters
hthe UriQueryInfo hash to serialize
arg_separatorthe character to use to separate URI query arguments
Since
Util 1.3

◆ normalize_dir()

string Util::normalize_dir ( string  path,
string  cwd = getcwd() 
)

returns a platform-specific normalized path name (starting from /, eliminates ".", "..", and "//")

Example:
string path = normalize_dir(path);

Currently only Windows and UNIX-style directories are supported; this function calls either:

Parameters
paththe path to normalize
cwdthe current working directory for normalizing relative paths
Returns
a normalized path name for the current platform
See also

◆ normalize_dir_unix()

string Util::normalize_dir_unix ( string  path,
string  cwd = getcwd() 
)

returns a normalized UNIX path name (starting from /, eliminates ".", "..", and "//")

Example:
string path = normalize_dir_unix(path, "/var/tmp");

For example, calling:

normalize_dir("../../test/.//dir");

from current directory "/opt/qorus/sub/dir" returns:

"/opt/qorus/test/dir"
Parameters
paththe path to normalize
cwdthe current working directory
Returns
a normalized path name (starting from /, eliminates ".", "..", and "//")

◆ normalize_dir_windows()

string Util::normalize_dir_windows ( string  path,
string  cwd = getcwd() 
)

returns a normalized Windows path name (eliminates ".", "..", and "//")

Example:
string path = normalize_dir_windows(path, "c:\\qore"));

For example, calling:

normalize_dir("..\..\test\.\\dir");

from current directory "c:\\lang\\qore\\prog1" returns:

"c:\\lang\\test\\dir"
Parameters
paththe path to normalize
cwdthe current working directory
Returns
a normalized path name; eliminates ".", "..", and "\\" (except at the beginning of a UNC path)

◆ ordinal()

string Util::ordinal ( int  i)

Returns string with partially textual representation of ordinal integer value.

Example:
printf("%s grade", ordinal(1));
# would print "1st grade"
string printf(string fmt,...)
Parameters
iinteger value to convert to textual representation
Returns
a string representation of ordinal value of the argument
Since
Util 1.2

◆ parse_memory_size()

int Util::parse_memory_size ( string  str,
*bool  use_binary 
)

Returns a size in bytes from a string where "1M" = 1048576 and so forth.

Parameters
strthe input string to parse
use_binaryif True then base-2-based values are always assumed (i.e. "1 KB" = 1024 bytes and so forth)
Returns
the size in bytes

Known suffixes:

  • K, KiB = one Kibibyte (1024 bytes)
  • M, MiB = one Mebibyte (1024 * 1024 bytes)
  • G, GiB = one Gibibyte (1024 * 1024 * 1024 bytes)
  • KB = 1,000 bytes (i.e. a "marketing kilobyte")
  • MB = 1,000,000 bytes (i.e. a "marketing megabyte")
  • GB = 1,000,000,000 bytes (i.e. a "marketing gigabyte") . and so on
Exceptions
MEMORY-SIZE-ERRORcannot parse string

◆ parse_ranges()

list<int> Util::parse_ranges ( string  text)

Parses a string and returns a list of integers.

Parameters
textthe string to parse
Returns
a list of integer numbers
Example:
list<int> ints = parse_ranges("3,5, 7-9"); # returns (3, 5, 7, 8, 9)
Since
Util 1.4

◆ parse_to_qore_value()

auto Util::parse_to_qore_value ( string  arg)

tries to convert a string (such as an argument given from the command-line) to a Qore value

This function recognizes two special prefixes in the string:

  • STR= this prefix indicates that the rest of the string should be passed literally and not parsed
  • EVAL= this prefix indicates that the rest of the string should be taken as a Qore expression and executed and the value returned

Strings are interpreted as in the following table.

String Parsing

Format Description
key_string = value[, ...] a hash
value, [...] a list
integers an integer
floats a float
arbitrary-numeric value a number
True, true, False, false a bool
YYYY-MM-DD[[-T ]HH:mm[:SS[.uu]]] a date
a Qore expression the value evaluated
a quoted string a string
Examples:
prompt% qore -l Util -X 'parse_to_qore_value("(a=(b=(c=x, 2, 3)))")'
hash: (1 member)
  a : hash: (1 member)
    b : list: (3 elements)
      [0]=hash: (1 member)
        c : "x"
      [1]=2
      [2]=3
Parameters
arga string to convert to a Qore value according to the rules documented above
Returns
the Qore value corresponding to the input string
Exceptions
PARSE-ERRORcannot parse the string given
See also
serialize_to_string() as a related serialization function

◆ parse_uri_query()

hash<UriQueryInfo> Util::parse_uri_query ( string  path)

parses a URI path for a arguments and a method; where the method is the part of the path before the first "?" character, and arguments are after

Parameters
paththe URI path to parse
Returns
a UriQueryInfo hash
Note
the params output key value is always returned as a hash
Since
Util 1.3

◆ plural()

string Util::plural ( int  count,
string  base,
string  singular = '',
string  plural = 's' 
)

Returns string with number and proper singular/plural form of noun.

Parameters
countinteger value to convert
basebase word or possibly nothing
singularsingular form suffix or whole word
pluralplural form suffix or whole word
Returns
a string representation of number plus noun
Example:
printf (plural(1, "beer"));
# would print "1 beer"
printf (plural(1, "lad", "y", "ies"));
# would print "1 lady"
printf (plural(32, "", "tooth", "teeth"));
# would print "32 teeth"
Since
Util 1.2

◆ regex_escape()

string Util::regex_escape ( string  text)

Escapes (backslashes) all non-alphanumeric characters in a string.

Returns string with all non-alphanumerics backslashed; this is useful if you want to match an arbitrary literal string that may have regular expression metacharacters in it.

Parameters
textstring to escape / backslash
Returns
a string escaped / backslashed
Example:
string s = regex_escape ("Gain: $100"); # returns "Gain\\:\\ \\$100"
Since
Util 1.2

◆ rpad()

string Util::rpad ( softstring  text,
int  length,
string  padding = ' ' 
)

Returns a string right-padded to a specified length with the specified characters.

Returns a string, right-padded to a specified length with the specified characters; or, when the string to be padded is longer than the length specified after padding, only that portion of the string that fits into the specified length.

Parameters
textinput string that you want to pad
lengthtotal length of output string (in characters)
paddingpadding character(s); default value is a single blank
Returns
a string right-padded to the specified length
Example:
string s = rpad ("123", 5); # returns "123 "
string s = rpad ("ABC", 9, "-"); # returns "ABC------"
Since
Util 1.2

◆ same()

bool Util::same ( list< auto >  l)

checks whether given list has only unique elements

Example:
if (same((1, 1, 1)) {
printf("only unique elements");
};
Parameters
lsome list
Since
Util 1.2

◆ serialize_to_string()

string Util::serialize_to_string ( auto  val)

Serializes the given value to a string that can be deserialized with parse_to_qore_value()

Parameters
valthe value to serialize to a string
Returns
the string value reprepsenting the argument; note that this value can be passed to parse_to_qore_value() as an argument to be deserialized
Note
  • This API is meant for serialization of simple types to readable strings only; for proper serialization, see Qore::Serializable
  • Only string, int, float, bool, date (absolute), list, and hash values are supported
Exceptions
SERIALIZATION-ERRORcannot serialize data type
See also
Since
Util 1.7

◆ slice()

list<auto> Util::slice ( list< auto >  l,
softlist< auto >  indices 
)

list slice implementation

Example:
list<string> l = slice(("a", "b", "c", "d"), (1, 3)); # returns ("b", "d")
Parameters
lsome list
indicesindices that should be sliced from the original list
Since
Util 1.2

◆ string_ends_with()

bool Util::string_ends_with ( string  str,
string  substr 
)

Verifies whether a string ends with specific substring.

Parameters
strstring to be checked
substrsubstring to look for at str's end
Returns
True if str ends with substr, False otherwise

◆ string_starts_with()

bool Util::string_starts_with ( string  str,
string  substr 
)

Verifies whether a string begins with specific substring.

Parameters
strstring to be checked
substrsubstring to look for at str's start
Returns
True if str starts with substr, False otherwise

◆ substitute_env_vars()

string Util::substitute_env_vars ( string  str)

Substitutes environment variables in a string and returns the string.

Parameters
strthe string to process
Returns
the string with environment variables substituted
Since
Util 1.5.1

◆ tmp_location()

string Util::tmp_location ( )

Returns a path for temporary files.

Example:
string testfile = tmp_location() + '/test.txt';
# some processing
unlink(testfile);

Environment variables are searched in the following order (the first with a value is used):

  • TMPDIR
  • TMP
  • TEMP
  • TEMPDIR

If none of these are present, then "/tmp" (UNIX) or "c:\temp" (Windows) is checked.

Exceptions
TMP-ERRORunable to find the location of the temporary directory; temporary directory is not writable
Since
Util 1.2

◆ uniq()

list<auto> Util::uniq ( softlist< auto >  arg)

Returns a duplicate-free version of the list.

Parameters
arga list of values to filter out
Returns
a list of unique values
Example:
list<auto> u = uniq((1,2,1,3,2,1)); # returns (1,2,3)
Note
Since the implementation of this function uses a hash to keep track of the list values, it cannot process values that cannot be coverted to strings or for which implicit string representation collide (e.g. float values that differ outside implicit toString() precision).
Exceptions
UNIQ-ERRORif two different values from the list share the same implicit string representation
Since
Util 1.3

◆ zip()

list<auto> Util::zip ( )

Returns a list of lists, where the i-th list contains the i-th element from each of the argument lists.

Parameters
...lists to 'zip'
Returns
a list of lists
Example:
list z = zip ((1, 2, 3), (4, 5)); # returns ((1,4), (2,5), (3,NOTHING))
Since
Util 1.2