TCE v1.1 language reference

Introduction

Tiered category expressions (TCEs) are written in a language specifically designed for matching tiered categories.

A tiered category is defined as a list of tiers where the left most tier is the most generic one (root) and each subsequent tier is a specification (child) of its predecessor (parent). Describing a path through the category tree, up from the root. For instance:

["AGF", "Groente", "Komkommer"]

TCEs follow the same structure. They consist of category tier names separated by special separators. Here are some examples to get an idea of what TCEs look like:

• agf > groente
• agf > groente > komkommer
• agf > groente > komkommer.
• agf > groente > kom%
• agf > groente | fruit > komkommer
• agf > groente > !tomaat
• agf >> komkommer
• >> komkommer

All of these examples match the category ["AGF", "Groente", "Komkommer"]. The syntax is explained in more detail in the next section.

When a TCE is matched with a category:

• Letter case is ignored, e.g. both "NONFOOD" and "NonFood" match "nonfood" and vice versa.
• Everything other than alphabetic and numeric characters (including spaces) is ignored, e.g. "nonfood" matches both "non-food" and "non food".
• Accents are ignored, e.g. "knäckebröd" matches "knackebrod" and vice versa.
• By default it matches a subtree of categories, e.g. the TCE "nonfood" matches the category ["Nonfood"] as well as ["Nonfood", "Schoonmaak", "Soda"].

Even though they are ignored, tier names in TCEs may contain spaces, upper and lowercase characters and accented characters. To the contrary, they cannot contain special characters.

# Invalid
"Brood & deegwaren > Volkoren-knäckebröd"

# Valid
"Brood deegwaren > Volkoren knäckebröd"

Note that TCEs are considered equal if they match the same categories. E.g. these TCEs are equal:

"brood crackers > knäckebröd"
"brood crackers > KNACKEBROD"
"broodcrackers > k n ä c k e b r ö d"

Syntax

Matching direct children >

"agf > groente > komkommer"

# Matches
["AGF", "Groente", "Komkommer"]
["AGF", "Groente", "Komkommer", "Snack komkommer"]

# Does not match
["AGF", "Groente"]
["AGF", "Groente", "Tomaat"]
["Groente & fruit", "Groente", "Komkommer"]

Matching descendants at any depth >>

"agf >> komkommer"

# Matches
["AGF", "Komkommer"]
["AGF", "Komkommer", "Snack komkommer"]
["AGF", "Groente", "Komkommer", "Snack komkommer"]

# Does not match
["AGF"]
["AGF", "Snack komkommer"]
["AGF", "Groente", "Snack komkommer"]

Wildcards %

"groente% > %komkommer"

# Matches
["Groente", "Komkommer"]
["Groente & fruit", "Snack komkommer"]

Negation !

"!komkommer"

# Does not match
["Komkommer"]

Lists |

"veldsla | ijsbergsla | rucola"

# Matches
["Veldsla"]
["IJsbergsla"]
["Rucola"]

Explicit last tier(s) .

"agf > groente > komkommer."

# Matches
["AGF", "Groente", "Komkommer"]

# Does not match
["AGF", "Groente", "Komkommer", "Snack komkommer"]

"agf > groente. > komkommer"

# Matches
["AGF", "Groente"]
["AGF", "Groente", "Komkommer"]
["AGF", "Groente", "Komkommer", "Snack komkommer"]

# Does not match
["AGF", "Groente", "Tomaat"]

"agf > groente. > komkommer."

# Matches
["AGF", "Groente"]
["AGF", "Groente", "Komkommer"]

# Does not match
["AGF", "Groente", "Tomaat"]
["AGF", "Groente", "Komkommer", "Snack komkommer"]

Combining patterns

"groente > seizoensgroente > %"

# Matches
["Groente", "Seizoensgroente", "Pastinaak"]
["Groente", "Seizoensgroente", "Vers", "Pastinaak"]

# Does not match
["Groente", "Seizoensgroente"]

">> !komkommer%"

# Does not match
["Komkommer"]
["Komkommer & fruit"]
["AGF", "Komkommer"]
["AGF", "Komkommer & fruit"]
["AGF", "Groente", "Komkommer"]

"nonfood >> ! babyvoeding | diervoeding"

# Matches
["Nonfood", "Baby", "Flessen"]
["Nonfood", "Huisdier", "Aanlijnriemen"]

# Does not match
["Nonfood", "Baby", "Babyvoeding"]
["Nonfood", "Huisdier", "Diervoeding"]
["Nonfood", "Babyvoeding"]
["Nonfood", "Diervoeding"]
["Nonfood"]

"voeding. >> %voeding."

# Matches
["Voeding"]
["Voeding", "Babyvoeding"]
["Voeding", "Diervoeding"]
["Voeding", "Baby", "Babyvoeding"]
["Voeding", "Dier", "Diervoeding"]

# Does not match
["Voeding", "AGF"]
["Voeding", "Babyvoeding", "Newborn"]
["Voeding", "Diervoeding", "Hond"]
["Voeding", "Baby", "Babyvoeding", "Newborn"]
["Voeding", "Dier", "Diervoeding", "Hond"]