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String Functions

The string handling functions operate on strings. Many have Python equivalents and behave similarly.

alter(value, value, value)

Alters the first string by substituting the third string for every instance of the second string.

    @altered = alter("the quick brown dog", "dog", "fox")
    @altered == "the quick brown fox" -> print("Yes, that's right")

caps(value, value)

Uppercases the initial character of a string. If the optional second argument evaluates to True (e.g. yes()) the string is split on a space (" ") and each substring's initial char is uppercased.

concat(value, value, ...)

Concatenates any number of strings.

length(value)

Same as you would expect.

min_length(value, int) and max_length(value, int)

min_length() and max_length() return True if the stringified value is more than or less than the integer provided. The functionality can also be achieved using above() and below() or between(), but the min and max functions are obviously simpler. Likewise, there is overlap with the newer string(); however, you cannot use string() to set a min without also setting a max; for that you would need min_length().

string(value, max, min)

string() is an evolved approach that enables a simpler declaration of a string. Think of it like a VARCHAR declaration in SQL's DDL. You can add the notnone qualifier to force string() to be not None. string() stringifies its value. The value of string() is the value it wraps. Standing alone it is an existance test that the wrapped value is not None.

lower(value)

Lowercases a string.

starts_with(does_this, start_with_this)

Checks if the first value, stringified, starts with the second value. The values are stripped. Alias: startswith(). If either value is none() or None the result is False. If the second value is "" the result is False.

ends_with(does_this, end_with_this)

Checks if the first value, stringified, ends with the second value. The values are stripped. Alias: endswith(). If either value is none() or None the result is False. If the second value is "" the result is False.

strip(value)

Trims whitespace. Same as you would expect from the Python function.

substring(value, int)

Substring starting from left and including the number of characters indicated. The value is stringified, so you can substring essentially anything. Unlike Python, for clarity CsvPath does not allow negatives.

upper(value)

Uppercases a string.

Examples

    $file.csv[*][
        @name = concat( #firstname, " ", #lastname )
        @name = strip(@name)
        @len = length(#firstname)
        @first = substring(@name, @len)
        @lower = lower(@name)
        @badge = upper(value)
    ]

This csvpath uses the string functions in their obvious ways.

    $file.csv[*][
        @name = #firstname
        @name_length = length(@name)
        gt(@name_length, 12) -> @name = substring(#firstname, 9)
        length(@name) == 9 -> @name = concat(@name, "...")
        print("Welcome $.variables.name")
    ]

This csvpath does backflips to get a truncated name, mainly proving that CsvPath is not a programming language. Validation is enough.