Enable case-sensitive comparison. With these directives, "ABC" and "abc" are considered different.

Enable case-insensitive comparison (default behavior). With these directives, "ABC" and "abc" are considered identical.

Enable filter expression optimization (default behavior). This may improve performance for complex expressions.

Disable filter expression optimization. This is useful for debugging or when optimization causes unexpected results.

Assigns a name to the filter expression. If the name contains spaces or special characters, it must be enclosed in double quotes. Names without spaces can be specified without quotes.

The specified name will be used in error messages and diagnostic output to identify the filter. This is particularly useful when working with multiple complex filter expressions.

Returns true if the file exists, false otherwise

File name

Returns the filename without extension. For example, "document.txt" returns "document".

File extension

Returns true if the item is a folder/directory, false if it's a file.

Returns the relative path excluding the file name and base folder

Returns the relative path from the comparison root directory, including both folder path and filename. For example, if comparing "C:\Project" and the file is at "C:\Project\src\main.cpp", RelPath returns "src\main.cpp".

Returns the full path of the file

File size

Last modified timestamp

Last modified date string in yyyy-MM-dd format

Creation date timestamp

Returns the file attributes as an integer value

Returns file attribute string. Examples: "R" for Read-only, "H" for Hidden, "A" for Archive, "S" for System file.

Content of the file. Returns a FileContent-type value. Only contains and recontains can be used with this type.

Number of files directly contained in the folder.

Number of files contained in the folder, including all subfolders.

Number of items (files and subfolders) directly contained in the folder.

Number of items (files and subfolders) contained in the folder, including all subfolders.

Total size of all files directly contained in the folder, in bytes.

Total size of all files contained in the folder, including all subfolders, in bytes.

Returns an array of property values (Left, Middle, Right) for the specified canonical property name. Example: prop("System.Title")

Property value of the left-side file. Example: leftprop("System.FileOwner")

Property value of the middle file (in 3-way comparison).

Property value of the right-side file.

Returns true if the comparison result indicates the items are identical, false otherwise. This is a global attribute (does not support side-specific prefixes). Example: Identical to show only identical files.

Returns true if the comparison result indicates the items are different, false otherwise. This is a global attribute (does not support side-specific prefixes). Example: Different to show only different files.

Returns true if the comparison was skipped due to an error or filter rule, false otherwise. This is a global attribute (does not support side-specific prefixes). Example: Skipped to show only skipped items.

Returns true if the file is detected as binary, false if it's text, or none if the file doesn't exist. This attribute supports side-specific prefixes (e.g., LeftBinary, RightBinary). Example: allof(Binary) to show files that are binary on all sides.

Returns true if the left and middle files are different in a 3-way comparison, false otherwise. Returns none in 2-way comparisons. This is a global attribute (does not support side-specific prefixes). Example: DifferentLeftMiddle and not DifferentMiddleRight to find files where only left differs from middle.

Returns true if the middle and right files are different in a 3-way comparison, false otherwise. Returns none in 2-way comparisons. This is a global attribute (does not support side-specific prefixes). Example: DifferentMiddleRight to show files where middle and right differ.

In 3-way comparisons, returns true if the left and right files are different, false otherwise. In 2-way comparisons, returns true if both files exist and are different. This is a global attribute (does not support side-specific prefixes). Example: DifferentLeftRight to show files where left and right differ.

Returns the number of text differences in the file comparison. This attribute is only meaningful for text files that have been compared. This is a global attribute (does not support side-specific prefixes). Example: Differences > 0 to show files with differences, or Differences > 10 to show files with more than 10 differences.

Returns the number of ignored differences in the file comparison (differences filtered by line filters or whitespace settings). This attribute is only meaningful for text files that have been compared. This is a global attribute (does not support side-specific prefixes). Example: IgnoredDiffs > 0 to show files with ignored differences, or Differences = 0 and IgnoredDiffs > 0 to show files that are identical except for ignored differences.

Returns the name of the unpacker plugin used for the file comparison, or an empty string if no unpacker was used. This is a global attribute (does not support side-specific prefixes). Example: Unpacker = "CompareMSExcelFiles" to show files compared using the Excel unpacker, or Unpacker != "" to show all files where an unpacker was used.

Returns the name of the prediffer plugin used for the file comparison, or an empty string if no prediffer was used. This is a global attribute (does not support side-specific prefixes). Example: Prediffer = "IgnoreColumns" to show files compared using the IgnoreColumns prediffer, or Prediffer != "" to show all files where a prediffer was used.

Returns the end-of-line (EOL) style as an integer value. For files, returns the predominant EOL style; for lines, returns the EOL style of that specific line.

Values: 0 = None, 1 = LF (Unix), 2 = CR (Mac), 3 = CRLF (Windows), 4 = Mixed (multiple EOL styles in file)

Returns the end-of-line (EOL) style as a string. For files, returns the predominant EOL style; for lines, returns the EOL style of that specific line.

Values: "None", "LF", "CR", "CRLF", "Mixed"

Returns the file's codepage (character encoding) as an integer value. This attribute supports side-specific prefixes (e.g., LeftCodepage, RightCodepage). Example: Codepage = 65001 to show UTF-8 files, or allof(Codepage = 65001) to show files that are UTF-8 on all sides.

Returns true if the file has a Byte Order Mark (BOM), false otherwise. This attribute supports side-specific prefixes (e.g., LeftHasBOM, RightHasBOM). Example: HasBOM to show files with BOM, or not HasBOM to show files without BOM.

Returns the length of the string as an Integer. If source is a string array, the result is an integer array. Example: strlen(Name)

Counts how many times the substring substr appears in str. The search is case-insensitive by default (respects @cs/@ci directives). If str is an array, the result is an integer array with counts for each element. Overlapping matches are counted separately (e.g., strCount("aaaa", "aa") returns 2).

Examples:

Counts how many times the regular expression pattern matches in str. The search is case-insensitive by default (respects @cs/@ci directives). If str is an array, the result is an integer array with counts for each element. Zero-length matches are handled gracefully to avoid infinite loops.

Examples:

Finds the position (0-based) of the Nth occurrence of substring substr in str. The optional occurrence parameter specifies which occurrence to find (0-based, default is 0 for the first occurrence). The search is case-insensitive by default (respects @cs/@ci directives). Returns none if the substring is not found or if the occurrence index is out of range. If str is an array, the result is an array of positions (or none values).

Examples:

Finds the position (0-based) of the Nth occurrence of a regular expression match in str. The optional group parameter specifies which capture group to locate (0-based, default is 0 for the entire match). The optional occurrence parameter specifies which occurrence of the pattern to find (0-based, default is 0 for the first occurrence). The search is case-insensitive by default (respects @cs/@ci directives). Returns none if the pattern doesn't match, the group index is out of range, or the occurrence index is out of range. If str is an array, the result is an array of positions (or none values).

Examples:

Returns a specific range of text from the string or string array as a String. If source is a string array, the result is a string array. Example: substr(Name, 0, 3)

Replaces all occurrences of the string from with to. If str is an array, the result is an array of strings with replacements applied. Example: replace(name, ".bak", ".txt")

Replaces all matches of the regular expression pattern with the replacement string. Supports backreferences ($1, $2, etc.) in the replacement string. If str is an array, the result is an array of strings with replacements applied. Example: regexReplace(name, "^(\w+)_(\w+)$", "$2_$1") swaps words separated by underscore.

Replaces multiple strings in str using replacement rules loaded from a tab-separated file. The file format is one replacement rule per line: search_string<TAB>replacement_string. Lines starting with # are treated as comments and ignored. Empty lines are also ignored. If str is an array, the result is an array of strings with replacements applied.

File format example:

# Comment line
apple	orange
cat	dog
old	new

Examples:

Replaces strings in str using regular expression patterns loaded from a tab-separated file. The file format is one pattern per line: regex_pattern<TAB>replacement_string. The replacement string can include backreferences ($1, $2, etc.) to captured groups. Lines starting with # are treated as comments and ignored. Empty lines are also ignored. If str is an array, the result is an array of strings with replacements applied.

File format example:

# Comment line
\d+	NUMBER
(\d{4})-(\d{2})-(\d{2})	$1_$2_$3

Examples:

Captures text matching a regular expression pattern from the string. The optional group parameter specifies which capture group to extract (0-based). Group 0 (default) returns the entire match; groups 1, 2, etc. return the corresponding capture groups defined by parentheses in the pattern. The optional offset parameter specifies which occurrence of the pattern to capture (0-based). Offset 0 (default) returns the first match; offset 1 returns the second match, etc. This is useful for capturing the Nth occurrence in a line, such as the second number in a string. Returns none if the pattern doesn't match, the group index is out of range, or the offset exceeds the number of matches. If str is an array, the result is an array with captures for each element. The search is case-insensitive by default (respects @cs/@ci directives).

Examples:

Normalizes Unicode string. The optional form parameter specifies the normalization form: "NFC" or "C" (default), "NFD" or "D", "NFKC" or "KC", "NFKD" or "KD". Can also use numeric forms: 1=NFC, 2=NFD, 5=NFKC, 6=NFKD. If str is an array, the result is an array of normalized strings. Example: normalizeUnicode(name, "NFC")

Converts all characters in the string to lowercase. If str is an array, the result is an array of lowercase strings. Example: toLower("Hello World") returns "hello world"

Converts all characters in the string to uppercase. If str is an array, the result is an array of uppercase strings. Example: toUpper("Hello World") returns "HELLO WORLD"

Converts full-width characters to half-width characters. Primarily used for converting full-width alphanumeric and katakana characters to half-width. If str is an array, the result is an array of converted strings.

Converts half-width characters to full-width characters. Primarily used for converting half-width alphanumeric and katakana characters to full-width. If str is an array, the result is an array of converted strings.

Converts hiragana characters to katakana. Non-hiragana characters remain unchanged. If str is an array, the result is an array of converted strings.

Converts katakana characters to hiragana. Non-katakana characters remain unchanged. If str is an array, the result is an array of converted strings.

Converts traditional Chinese characters to simplified Chinese characters. Characters that don't have a simplified form remain unchanged. If str is an array, the result is an array of converted strings.

Converts simplified Chinese characters to traditional Chinese characters. Characters that don't have a traditional form remain unchanged. If str is an array, the result is an array of converted strings.

Removes leading and trailing whitespace characters (space, tab, newline, carriage return) from the string. If str is an array, the result is an array of trimmed strings.

Examples:

Removes leading whitespace characters (space, tab, newline, carriage return) from the beginning of the string. Trailing whitespace is preserved. If str is an array, the result is an array of left-trimmed strings.

Examples:

Removes trailing whitespace characters (space, tab, newline, carriage return) from the end of the string. Leading whitespace is preserved. If str is an array, the result is an array of right-trimmed strings.

Examples:

Returns the number of lines in the file content or file content array as an Integer. If content is an array, the result is an integer array. Example: lineCount(Content)

Extracts the specified number of lines starting from the given line index in the file content or file content array, and returns them as a single concatenated string. If content is an array, the result is an array of strings.

Convert a string to a number. toNumber returns an integer or floating-point number depending on the input format; toInt returns only integers; toDouble returns only floating-point numbers. Commas in the input are ignored. Returns noneon parse failure. Example: le:toInt(Column("Count")) > 100

Converts a string to a timestamp value. Supports multiple date/time formats. Returns noneif the string cannot be parsed. Example: toDateTime("2025-01-15") > today()

Returns the current date and time as a Timestamp value.

Returns today's date as a Timestamp value representing 00:00:00.000 at the start of the day.

Returns the first day of the week, which is always Sunday regardless of locale.

Returns the first day of the month.

Returns the first day of the year.

Converts the given timestamp to a date string in yyyy-MM-dd format. If timestamp is a timestamp array, the result is a string array.

Returns the absolute value of the integer or integer array. If value is an integer array, the result is an integer array.

Returns true if value is within the range [min, max] (inclusive on both ends). Supports integers, floating-point numbers, timestamps, and strings (case-insensitive comparison). If value is an array, the result is a boolean array with each element checked individually.

Examples:

Returns true if value is within the range [min, max) (inclusive on the lower bound, exclusive on the upper bound). Supports integers, floating-point numbers, timestamps, and strings (case-insensitive comparison). If value is an array, the result is a boolean array with each element checked individually.

Examples:

Creates an array from the given values. Example: array(1, 2, 3)

Returns the element at the specified index (0-based). Negative indices count from the end. Example: at(array(1, 2, 3), -1) returns 3

Returns true if any element in the boolean array satisfies the condition.

Returns true if all elements in the boolean array satisfy the condition.

Returns true if all values in the array are equal.

Returns the length of the value as an Integer.

Behavior:

Examples:

Returns trueValue if condition evaluates to true, otherwise returns falseValue. This function performs short-circuit evaluation (it only evaluates the branch that will be returned).

Examples:

Element-wise conditional selection. For each element in conditionArray, returns the corresponding element from trueValue if the condition is true, otherwise returns the corresponding element from falseValue. If trueValue or falseValue is a scalar, it is broadcast to all elements.

Examples:

Selects a value from the arguments based on index. If index is 0, returns value0; if 1, returns value1, etc. Negative indices are clamped to 0. Indices beyond the last value return the last value.

Examples:

Element-wise value selection. For each index in indexArray, selects the corresponding value from the remaining arguments. If indexArray is a scalar, behaves like choose.

Examples:

Element-wise logical operations. These functions operate on booleans, boolean arrays, or a combination of both:

When arguments are scalars, returns a scalar boolean result. When one argument is an array and the other is a scalar, the scalar is broadcast to all elements. When both arguments are arrays, performs element-wise operation.

Examples:

Outputs the concatenated string representation of all arguments to the log (at error, warning, or information level respectively), separated by spaces, and returns the last argument value. These functions are useful for debugging filter expressions.

Examples (using return value):