> For the complete documentation index, see [llms.txt](https://docs.zama.org/tfhe-rs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zama.org/tfhe-rs/fhe-computation/operations/string-operations.md). # String operations This document details the string operations supported by **TFHE-rs**. | clear name | fhe name | first input type | second input type | third input type | | -------------------------------------------------------------------------------------------------------------- | ---------------- | ---------------- | ---------------------------------------------- | ---------------------------------------------- | | [eq](https://doc.rust-lang.org/stable/std/primitive.str.html#method.eq) | eq | FheAsciiString | FheAsciiString or ClearString | | | [ne](https://doc.rust-lang.org/stable/std/primitive.str.html#method.ne) | ne | FheAsciiString | FheAsciiString or ClearString | | | [le](https://doc.rust-lang.org/stable/std/primitive.str.html#method.le) | le | FheAsciiString | FheAsciiString or ClearString | | | [ge](https://doc.rust-lang.org/stable/std/primitive.str.html#method.ge) | ge | FheAsciiString | FheAsciiString or ClearString | | | [lt](https://doc.rust-lang.org/stable/std/primitive.str.html#method.lt) | lt | FheAsciiString | FheAsciiString or ClearString | | | [gt](https://doc.rust-lang.org/stable/std/primitive.str.html#method.gt) | gt | FheAsciiString | FheAsciiString or ClearString | | | [len](https://doc.rust-lang.org/stable/std/primitive.str.html#method.len) | len | FheAsciiString | | | | [is\_empty](https://doc.rust-lang.org/stable/std/primitive.str.html#method.is_empty) | is\_empty | FheAsciiString | | | | [eq\_ignore\_ascii\_case](https://doc.rust-lang.org/stable/std/primitive.str.html#method.eq_ignore_ascii_case) | eq\_ignore\_case | FheAsciiString | FheAsciiString or ClearString | | | [to\_lowercase](https://doc.rust-lang.org/stable/std/primitive.str.html#method.to_lowercase) | to\_lowercase | FheAsciiString | | | | [to\_uppercase](https://doc.rust-lang.org/stable/std/primitive.str.html#method.to_uppercase) | to\_uppercase | FheAsciiString | | | | [contains](https://doc.rust-lang.org/stable/std/primitive.str.html#method.contains) | contains | FheAsciiString | FheAsciiString or ClearString | | | [ends\_with](https://doc.rust-lang.org/stable/std/primitive.str.html#method.ends_with) | ends\_with | FheAsciiString | FheAsciiString or ClearString | | | [starts\_with](https://doc.rust-lang.org/stable/std/primitive.str.html#method.starts_with) | starts\_with | FheAsciiString | FheAsciiString or ClearString | | | [find](https://doc.rust-lang.org/stable/std/primitive.str.html#method.find) | find | FheAsciiString | FheAsciiString or ClearString | | | [rfind](https://doc.rust-lang.org/stable/std/primitive.str.html#method.rfind) | rfind | FheAsciiString | FheAsciiString or ClearString | | | [strip\_prefix](https://doc.rust-lang.org/stable/std/primitive.str.html#method.strip_prefix) | strip\_prefix | FheAsciiString | FheAsciiString or ClearString | | | [strip\_suffix](https://doc.rust-lang.org/stable/std/primitive.str.html#method.strip_suffix) | strip\_suffix | FheAsciiString | FheAsciiString or ClearString | | | [concat](https://doc.rust-lang.org/stable/std/primitive.str.html#method.concat) | concat | FheAsciiString | FheAsciiString | | | [repeat](https://doc.rust-lang.org/stable/std/primitive.str.html#method.repeat) | repeat | FheAsciiString | u16 or u32 or i32 or usize or (FheUint16, u16) | | | [trim\_end](https://doc.rust-lang.org/stable/std/primitive.str.html#method.trim_end) | trim\_end | FheAsciiString | | | | [trim\_start](https://doc.rust-lang.org/stable/std/primitive.str.html#method.trim_start) | trim\_start | FheAsciiString | | | | [trim](https://doc.rust-lang.org/stable/std/primitive.str.html#method.trim) | trim | FheAsciiString | | | | [replace](https://doc.rust-lang.org/stable/std/primitive.str.html#method.replace) | replace | FheAsciiString | FheAsciiString | | | [replacen](https://doc.rust-lang.org/stable/std/primitive.str.html#method.replacen) | replacen | FheAsciiString | FheAsciiString or ClearString | u16 or u32 or i32 or usize or (FheUint16, u16) | The following example shows how to perform string operations: ```rust use tfhe::prelude::*; use tfhe::{ generate_keys, set_server_key, ConfigBuilder, FheAsciiString, }; fn main() -> Result<(), Box> { let config = ConfigBuilder::default().build(); let (client_key, server_key) = generate_keys(config); set_server_key(server_key); let string1 = FheAsciiString::try_encrypt("tfhe-RS", &client_key).unwrap(); let string2 = FheAsciiString::try_encrypt("TFHE-rs", &client_key).unwrap(); let is_eq = string1.eq_ignore_case(&string2); assert!(is_eq.decrypt(&client_key)); Ok(()) } ``` --- # Agent Instructions This documentation is published with GitBook. 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